LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 1
BAB IPENDAHULUAN
1.1 Latar Belakang
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
1.2 Tujuan Praktikum
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
2 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
BAB IITINJAUAN PUSTAKA
2.1 Pengertian Motor Bakar
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 3
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.2 Prinsip Kerja Motor Bakar Torak
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.2.1 Prinsip Kerja Motor Bakar Torak Berdasarkan Langkah Kerja
2.2.1.1 Motor Bakar Torak 2 Langkah
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
4 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.2.1.2 Motor Bakar Torak 4 Langkah
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.2.2 Prinsip Kerja Motor Bakar Torak Berdasarkan Sistem Penyalaan
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 5
2.2.2.1 Motor Bakar Diesel (Compression Ignition Engine)
A. Pengertian
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
B. Siklus Termodinamika
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
6 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
C. Rasio Kompresi
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.2.2.2 Motor Bakar Bensin (Spark Ignition Engine)
A. Pengertian
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 7
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
B. Siklus Termodinamika
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
C. Rasio Kompresi
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
8 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.3 Karakteristik Bahan Bakar
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.3.1 Flash Point
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 9
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.3.2 Fire Point
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.3.3 Auto-Ignition Point
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
10 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.3.4 Viskositas
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.3.5 Densitas
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 11
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.3.6 Nilai Kalor
A. High Heating Value (HHV)
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
B. Low Heating Value (LHV)
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
12 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.3.7 Octane Number
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.3.8 Cetane Number
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 13
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.4 Karakteristik Kinerja Motor Bakar
2.4.1 Indikator Kinerja Motor Bakar
A. Torsi
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
14 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
B. Daya Indikatif
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
C. Daya Efektif
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 15
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
D. Daya Mekanis
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
E. Mean Effective Pressure
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
16 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
F. Specific Fuel Consumption
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
G. Efisiensi
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 17
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
H. Air-Fuel Ratio dan Fuel-Air Ratio
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.4.2 Indikator Operasional Motor Bakar
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
18 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
A. Bukaan Katup (Throttle)
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
B. Beban Mesin
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 19
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.5 Hubungan Indikator Operasional terhadap Indikator Kinerja
2.5.1 Motor Bakar Diesel
2.5.1.1 Grafik Hubungan Putaran terhadap Torsi, Daya Efektif, dan SFC
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
20 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
....................................................................................................................................
....................................................................................................................................
A. Grafik Hubungan Putaran terhadap Torsi
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
B. Grafik Hubungan Putaran terhadap Daya Efektif
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 21
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
C. Grafik Hubungan Putaran terhadap SFC
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.5.1.2 Grafik Hubungan Putaran terhadap Daya Mekanis, Daya Indikatif,
dan MEP
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
22 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
A. Grafik Hubungan Putaran terhadap Daya Mekanis
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
B. Grafik Hubungan Putaran terhadap Daya Indikatif
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 23
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
C. Grafik Hubungan Putaran terhadap MEP
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.5.2 Motor Bakar Bensin
2.5.2.1 Grafik Hubungan Putaran terhadap Torsi, Daya Efektif, dan SFC
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
24 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
A. Grafik Hubungan Putaran terhadap Torsi
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
B. Grafik Hubungan Putaran terhadap Daya Efektif
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 25
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
C. Grafik Hubungan Putaran terhadap SFC
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
26 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
2.6 Governor Kecepatan
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.6.1 Karakteristik Governor
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 27
....................................................................................................................................
2.6.2 Tipe Governor
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.7 Orsat Apparatus
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
28 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.8 Diagram Sankey
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.9 Teknologi Motor Bakar Terbaru
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 29
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.9.1 Definisi
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.9.2 Tujuan
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
30 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.9.3 Prinsip Kerja
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.9.4 Kelebihan dan Kekurangan
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 31
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
2.9.5 Aplikasi dan Cara Perawatan
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
....................................................................................................................................
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
32 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
BAB IIIMETODE PENELITIAN
3.1 Waktu dan Tempat
Waktu :
Jam :
Tempat : Laboratorium Motor Bakar Teknik Mesin Universitas Brwaijaya
3.2 Pelaksanaan Praktikum
3.2.1 Instalasi Percobaaan Motor Diesel
Peralatan praktikum yang tersedia adalah instalasi percobaan (test rig)
lengkap, yang terdiri dari :
Instalasi Percobaan Motor Diesel
Unit Motor Diesel sebagai objek percobaan / penelitian.
Instrumen pengukur berbagai variabel yang diperlukan (barometer,
higrometer, aeorometer, orsat apparatus).
Peralatan bantu seperti instalasi air pendingin dan penyaluran gas buang.
Unit motor bakar yang digunakan adalah motor diesel dengan 4 silinder,
dengan spesifikasi sebagai berikut :
o Siklus : 4 langkah
o Jumlah silinder : 4
o Volume langkah torak total : 2164 cm3
o Diameter silinder : 83 mm
o Panjang langkah torak : 100 mm
o Perbandingan kompresi : 22 : 1
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 33
o Bahan bakar : Dexlite
o Pendingin : Air
o Daya Poros : 47 BHP / 3200 rpm
o Merk : Nissan, Tokyo Co.Ltd.
o Model : DWE – 47 – 50 – HS – AV
o Negara pembuat : Jepang
Gambar 3.1 Skema Instalasi Motor DieselSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
3.2.2 Alat Ukur dan Fungsinya
Alat ukur serta fungsinya yang digunakan saat praktikum adalah sebagai
berikut :
a. Orsat apparatus
Digunakan untuk mengukur dan menganalisa gas buang (%).
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
34 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
Gambar 3.2 Orsat apparatusSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
b. Barometer
Digunakan untuk mengukur tekanan atmosfer (mmHg).
Gambar 3.3 BarometerSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
c. Aerometer
Digunakan untuk mengukur massa jenis bahan bakar (kg/m3).
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 35
Gambar 3.4 AerometerSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
d. Flash Point
Digunakan untuk mengetahui titik nyala api suatu bahan bakar (oC).
Gambar 3.5 Flash PointSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
e. Diesel Engine Test Bed
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
36 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
Digunakan untuk mengetahui parameter-parameter yang menunjukkan
karakteristik motor bakar.
Gambar 3.6 Diesel Engine Test BedSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)f. Stopwatch
Digunakan untuk mengetahui waktu konsumsi bahan bakar (s)
Gambar 3.7 StopwatchSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
g. Hygrometer
Digunakan untuk mengukur kelembaban relatif udara (%).
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 37
Gambar 3.8 HygrometerSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
h. Dynamometer
Digunakan untuk mengetahui gaya pembebanan pada poros (Kg).
Gambar 3.9 DynamometerSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
i. Flowmeter air pendinginan
Digunakan untuk mengukur debit aliran air pendinginan (liter/jam).
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
38 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
Gambar 3.11 Flowmeter air pendinginanSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
j. Flowmeter Bahan Bakar
Digunakan untuk mengukur konsumsi bahan bakar (ml).
Gambar 3.12 Flowmeter bahan bakarSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 39
k. Manometer
Digunakan untuk mengukur perbedaan tekanan dalam system (mmH2O).
Gambar 3.13 ManometerSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
l. Viscometer
Digunakan untuk mengukur viskositas fluida (η).
Gambar 3.14 ViscometerSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
m. Bomb calorimeter
Digunakan untuk mengetahui kalor bahan bakar (Kcal/Kg)
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
40 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
Gambar 3.15 Bomb CalorimeterSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
n. STARGAS 898
Digunakan untuk menganalisis kandungan gas buang.
Gambar 3.16 STARGAS 898Sumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
3.3 Prosedur Pengambilan Data Praktikum
Setiap kelompok praktikum melaksanakan sendiri semua proses pengujian
dan pengambilan data yang diperlukan untuk memenuhi tujuan praktikum di atas.
Dalam melaksanakan proses pengujian tersebut, mahasiswa harus mengikuti
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 41
semua aturan dan tata tertib yang berlaku di laboratorium dan mengikuti semua
petunjuk asisten laboratorium yang bertugas.
Metode percobaan dengan variasi putaran, parameter yang diukur adalah :
1. Gaya Pengereman
2. Perbedaan Tekanan Masuk dan Keluar Nozzle
3. Kelembapan Udara
4. Suhu Gas Buang
5. Suhu Air Masuk dan Air keluar
6. Debit Bahan Bakar
7. Kandungan Gas Buang
8. Tekanan Udara
3.3.1 Prosedur Pengujian Motor Bakar
1. Persiapan Sebelum Mesin Beroperasi
a. Menyalakan pompa pengisi untuk mengisi air dalam tangki sampai level air
mencapai tinggi aman dan menyalakan cooling tower
b. Membuka kran air pada pipa-pipa yang mengalirkan air ke mesin dan ke
dinamometer.
c. Mengatur debit air yang mengalir pada flowmeter pada debit tertentu dengan
mengatur bukaan kran pada flowmeter.
d. Menekan switch power untuk menghidupkan alat-alat ukur.
e. Menghidupkan alarm air pendinginan yang akan memberitahu jika terjadi
overheating dan level air kurang.
f. Menyalakan dinamo power control dan atur kondisi poros mesin dalam
keadaan tanpa beban.
2. Cara Menghidupkan Mesin
a. Mengatur bukaan throttle sesuai yang diinginkan
b. Setelah semua persiapan di atas dipenuhi, menyalakan kunci kontak pada
posisi memanaskan mesin terlebih dahulu sampai indikator glow signal
menyala.
c. Memutar posisi kunci ke posisi START sambil mengurangi pembebanan
pada poros.
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
42 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
d. Setelah mesin menyala, biarkan mesin beroperasi beberapa saat untuk
menstabilkan kondisi mesin.
3. Cara Mengambil Data
a. Atur putaran mesin (rpm) dengan mengatur pembebanan pada dinamometer
sampai mendapatkan putaran yang diinginkan.
b. Tunggu kondisi mesin stabil kemudian lakukan pengambilan data yang
diperlukan.
3.3.2 Prosedur Penggunaan Orsat Apparatus
Gambar 3.17 Orsat ApparatusSumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
Cara penggunaan Orsat Apparatus :
1. Set ketiga tabung I, II, III pada ketinggian tertentu dengan membuka keran A,
B, C dan mengatur tinggi larutan pada tabung I, II, III dengan menaik –
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 43
turunkan gelas B, kemudian tutup keran A, B, C setelah didapatkan tinggi
yang diinginkan. Posisi ini ditetapkan sebagai titik acuan.
2. Naikkan air yang ada pada tabung ukur C sampai ketinggian air mencapai 50
ml dengan cara membuka keran H dengan menaikkan gelas B. Setelah
didapatkan tinggi yang diinginkan, tutuplah kembali keran H.
3. Ambil gas buang dari saluran gas buang untuk diukur, salurkan melalui
selang yang dimasukkan ke dalam pipa H.
4. Buka keran H sehingga gas buang akan masuk dan mengakibatkan tinggi air
yang ada di tabung ukur C akan berkurang.
5. Setelah tinggi air pada tabung ukur turun sebanyak 50 ml (sampai perubahan
air mencapai angka 0) tutuplah keran H dan kita sudah memasukkan volume
gas buang sebanyak 50 ml.
6. Untuk mengukur kandungan CO2 buka keran A supaya gas buang bereaksi
dengan larutan yang ada pada tabung III dengan mengangkat dan
menurunkan gelas B sebanyak 5 – 7 kali.
7. Setelah 5 – 7 kali kembalikan posisi larutan III ke posisi acuan pada saat set
awal dan tutup keran C setelah didapatkan posisi yang diinginkan.
8. Baca kenaikan permukaan air yang ada pada tabung ukur C. Kenaikan
permukaan air merupakan volume CO2 yang ada pada 50 ml gas buang yang
kita ukur.
9. Untuk mengukur kandungan O2 dan CO ulangi langkah 6 dan langkah 7
untuk keran B dan keran A pada tabung II dan tabung I.
10. Baca kenaikan permukaan air pada tabung ukur C dengan acuan dari tinggi
permukaan air sebelumnya.
3.3.3 Prosedur Penggunaan STARGAS 898
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
44 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
Gambar 3.18 STARGAS 898Sumber: Laboratorium Motor Bakar Jurusan Mesin Universitas Brawijaya (2019)
Cara Penggunaan STARGAS 898 :
1. Masukan gas probe pada pipa gas buang
2. Nyalakan STARGAS Gas Analyzer
3. Pilih fungsi MEASUREMENT pada halaman GAS ANALYSIS
4. Pilih fungsi STANDARD TEST pada halaman TEST SELECTION
5. Tekan MENU untuk menunjukkan FUNCTION BAR dalam halaman
measurement pada standard test
6. Print hasil analisis gas buang untuk percobaan pada putaran pertama.
7. Lepaskan gas probe dari pipa gas buang.
8. STARGAS Gas Analyzer berada pada kondisi Autozero
9. Ulangi dari langkah pertama untuk analisis gas pada percobaan kedua dan
selanjutnya.
3.3.4 Rumus Perhitungan
Adapun rumus – rumus yang digunakan dalam perhitungan hasil percobaan
adalah sebagai berikut :
1. Momen Torsi
T=F×l (kg.m) (3-1)
Dimana :
T : Torsi (kg.m)
F : besar gaya putar (kg)
L : panjang lengan dinamometer = 0,358 (m)
2. Daya Efektif
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 45
Ne= T×n716 ,2 (PS) (3-2)
Dimana :
n : putaran (rpm)
Ne : daya efektif (PS)
T : momen torsi (kg.m)
3. Daya Efektif dalam kondisi standard JIS
Neo=k . Ne (PS) (3-3)
k=749Pa−Pw √273+θ
293 ;
Pw=ϕ . PsDimana :
Neo : daya efektif yang dikonfersi dalam JIS (PS)
k : faktor konversi
Ne : daya efektif (PS)
Pa : tekanan atmosfir pengukuran (mmHg)
Pw : tekanan uap parsial (mmHg)
θ : rata-rata temperatur ruangan saat pengujian (°C)
ϕ : kelembamam udara (%)
Ps : Tekanan udara standar pada temperatur θ (mmHg)
4. Mean Effective Pressure (MEP)
Pe = Neo×0 , 45×z
Vd×i×n ( kg/cm2 ) (3-4)
Dimana :
Pe : tekanan efektif
z : jumlah putaran poros engkol
n : putaran poros engkol (rpm)
i : langkah mesin
Vd : volume langkah (m3)
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
46 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
5. Fuel Consumption
FC=Vt×ρ×3600
1000 (kg/jam) (3-5)
ρ dexlite = 0,836 gr/mL
Dimana :
FC : Konsumsi bahan bakar (kg/jam)
V : Volume bahan bakar (ml)
ρ : Massa jenis bahan bakar (gr/ml)
T : Waktu konsumsi bahan bakar (s)
6. Panas Hasil Pembakaran
Qb=FC x LHV (kcalJam
)
(3-6)
Dimana :
Qb : panas hasil pembakaran (kcal/jam)
FC : konsumsi bahan bakar (kg/jam)
LHV : Low Heating Value (kcal/kg)
7. Berat Jenis udara
γa=γo .× (Pa−ϕ . Ps )760
×273273+θ
+ϕ . γw
(3-7)
Dimana :
Pa : Tekanan atmosfer pengukuran (mmHg)
Ps : Tekanan udara standard pada temperatur tertentu (mmHg)
: Relative Humidity / Kelembapan Relatif (%)
o : Berat jenis udara kering pada 760 mmHg
: Temperatur bola kering(oC)
8. Koefisien Udara
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 47
ε=P1−P2
P1
(3-8)
Dimana :P1−P : beda tekanan pada nozzle (mmH2O)P1 : tekanan atmosfer saat pengujian (mmHg)
ε : koefisien udara
9. Massa alir udara melalui nozzle
Gs=α . ε . π . d2
4 √2 .g . γ a (P1−P2 ) (kg/s) (3-9)
Dimana :
Gs : Massa alir udara melalui nozzle (kg/s)
α : Koefisien kemiringan nozzle = 0,822
ɛ : Koefisien udara
d : diameter nozzle = 0,048 m
g : Gaya gravitasi = 9,81m/s2
γa : Berat jenis udara (kg/m3)
P1 – P2 : Perbedaan tekanan pada nozzle
10. Massa Alir gas buang
Gg=Gs+ FC3600 (kg/s) (3-10)
Dimana :
Gg : massa alir gas buang (kg/s)
Gs : massa alir udara melalui nozzle (kg/s)
FC : konsumsi bahan bakar (kg/jam)
11. Panas yang terbawa gas buang
Qeg=¿ . Cpg . (Teg−Tud ) x 3600 (kcal/jam) (3-11)
Dimana :
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
48 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
Cpg : panas jenis gas buang (kcal/kg.oC)
Teg : suhu gas buang (°C)
Tud : temperatur(°C)
Gg : massa alir gas buang (kg/s)
Qeg : panas yang terbawa gas buang (kcal/jam)
12. Efisiensi kerugian dalam exhaust manifold (ηg )
ηg=QegQb
x 100 %
(3-12)
Dimana :
ηg : efisiensi kerugian (%)
Qeg : panas yang terbawa gas buang (kcal/jam)
Qb : panas hasil pembakaran (kcal/jam)
13. Kerugian Panas Pendinginan (Qw)
Qw =ρ.Ww.Cpw (Two-Twi) (kcal/jam) (3-13)
Dimana :
ρ : Massa jenis air = 1 kg/liter
Ww : debit air pendinginan (liter/jam)
Cpw : panas jenis air = 1 kcal/kg.oC
Two : temperatur air keluar (oC)
Twi : temperatur air masuk (oC)
14. Efisiensi Kerugian Panas dalam cooling water(ηw )
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 49
ηw=QwQb
x 100 %
(3-14)
Dimana :
ηw : efisiensi kerugian panas (%)
Qw : kerugian panas pendinginan (kcal/jam)
Qb : panas hasil pembakaran (kcal/jam)
15. Efisiensi Thermal Efektif (ηe )
ηe=NeQb
×632×100 %
(3-15)
Dimana :
ηe : efisiensi efektif (%)
Ne : daya efektif (PS)
Qb : panas hasil pembakaran (kcal/jam)
16. Efisiensi Mekanis (η f )
η f=100 %−(ηg+ηw+ηe )(3-16)
Dimana :
η f : efisiensi gesekan (%)
ηg : efisiensi kerugian gas buang (%)
ηw : efisiensi kerugian air pendinginan (%)
ηe : efisiensi efektif (%)
17. Ekuivalen daya terhadap konsumsi bahan bakar (Qf )
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
50 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
Qf = LHV . FC632 (PS) (3-17)
Dimana :
LHV : Low Heating Value (kcal/kg)
FC : konsumsi bahan bakar (kg/jam)
18. Daya Mekanis
Nf =ηf xQf100 %
(3-18)
Dimana :
Nf : daya mekanis (PS)
η f : efisiensi gesekan (%)
Qf : kerugian karena gesekan (PS)
19. Daya IndikasiNi=Ne+Nm
(PS) (3-19)
Dimana :
Ni : daya indikasi (PS)
Ne : daya efektif (PS)
Nm : daya mekanis (PS)
20. Specific Fuel Consumption Effective
SFCe= FCNe
(3-20)
Dimana :
SFCe : Specific Fuel Consumption Effective
FC : konsumsi bahan bakar (kg/jam)
Ne : daya efektif (PS)
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 51
21. Specific Fuel Consumption Indicated
SFCi= FCNi
(3-21)
Dimana :
SFCi : Specific Fuel Consumption Indicated
FC : konsumsi bahan bakar (kg/jam)
Ni : daya indikatif (PS)
22. Panas Hasil Pembakaran yang diubah menjadi Daya Efektif
Qe=632. Ne(3-22)
Dimana :
Qe : panas efektif (kcal/jam)
Ne : daya efektif (PS)
23. Panas yang hilang karena sebab lain
Qpp=Qb−Qeg−Qw−Qe (3-23)
Dimana :
Qpp : panas yang hilang karena sebab lain (kcal/jam)
Qb : panas hasil pembakaran (kcal/jam)
Qeg : panas yang terbawa gas buang (kcal/jam)
Qw : kerugian panas pendinginan (kcal/jam)
Qe : panas efektif (kcal/jam)
24. Efisiensi Thermal Indikasi
ηi=NiQb
×632×100 %
(3-24)
Dimana :
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
52 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
ηi : efisiensi indikasi (%)
Ni : daya indikasi (PS)
Qb : panas hasil pembakaran (kcal/jam)
25. Efisiensi Mekanis
ηm=NeNi
x 100 %
(3-25)
Dimana :
ηm : efisiensi mekanis (%)
Ni : daya indikasif (PS)
Ne : daya efektif (PS)
26. Efisiensi Volumetrik
ηv=Gs . z . 60
γ a . n .Vd .ix 100 %
(3-26)
Dimana :
ηv : efisiensi volumetric (%)
z : jumlah poros engkol
Vd : volume engkol (m3)
I : langkah mesin
Gs : massa alir udara melalui nozzle (kg/s)
n : putaran poros (rpm)
γa : Berat jenis udara (kg/m3)
27. Perbandingan Udara dan Bahan Bakar
R= GsFC
x3600
(3-27)
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 53
Dimana :
R : rasio udara bahan bakar
Gs : aliran udara melalui nozzle (kg/s)
FC : konsumsi bahan bakar (kg/jam)
28. Rasio Udara Bahan Bakar Teoritis
C12, 3 H22+17 ,85(O2+3 ,76 N2 )→12,3 CO2+11 ,1 H2 O+67 , 116 N2
(3-28)
Ro=( A / F )s
(α+ β4 )M O2+3 , 76(α+ β
4 )M N2
α M C+β M HDimana :
Ro : Rasio udara bahan bakar teoritis
M O2 : Massa relatif oksigen
M N 2 : Massa relatif nitrogen
M C : Massa relatif karbon
M H : Massa relatif hidrogen
29. Faktor Kelebihan Udara
λ= RRo
(3-29)
Dimana : λ : faktor kelebihan udara
R : rasio udara bahan bakar
Ro : rasio udara dalam bahan bakar teoritis
30. Faktor Koreksi Standard
A=Pst
P [ TT st ]
0,5
=
P st
P [ T+273T st+273 ]
0,5
(3-30)
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GANJIL TAHUN AKADEMIK 2019/2020
54 | PRAKTIKUM MOTOR BAKAR KELOMPOK XX
Dimana :
A : faktor koreksi
Pst : tekanan atmosfer = 760 mmHg
Tst : 25 ˚C
P : tekanan udara atsmosfer (mmHg)
T : temperatur ruangan (oC)
31. Daya Efektif Standard
( Ne ) st=A . Ne(3-31)
Dimana :
( Ne ) st : daya efektif standar (PS)
A : faktor koreksi
Ne : daya efektif (PS)
32. Torsi Efektif Standard
(T )st=A . T(3-32)
Dimana :
(T )st : torsi efektif standar (kg.m)
A : faktor koreksi
T : torsi (kg.m)
33. Pemakaian Bahan Bakar Efektif Standard
( SFCe )st=SFCe
A(3-33)
Dimana :
LABORATORIUM MOTOR BAKAR FT - UBSEMESTER GENAP TAHUN AKADEMIK 2019/2020
PRAKTIKUM MOTOR BAKAR KELOMPOK XX | 55
SFCest : Pemakaian Bahan Bakar Efektif Standar
SFCe : Specific Fuel Consumption Effective
A : faktor koreksi
34. Analisa Gas Buang