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Kelompok 09
Adinda Sofura AzhariyahAfdhal Hanafi
Andrea Rizky HarahabManggala Pasca
Pangiastika Putri Wulandari
Soal 1Saturated steam at 0.276 MPa (0.276x106 Pascal) flows inside a steel pipe having inside diameter (I.D.) 2.09 cm and outside diameter (O.D.) 2.67 cm. k of the steel is 42.9 W/(m.K). The convective heat transfer coefficients on the inner and outer surfaces of the pipe are 5680 W/(m2.K) and 22.7 W/(m2.K), respectively. The surrounding air is at 294 K.
a. Find the heat loss per meter of the bare pipe (Watt/m).
b. Find the heat loss per meter (Watt/m) of the same pipe but insulated with 85% magnesia of 38 mm thickness (k value for 85% magnesia is 0.0675 W/(m.K))
a
r1
r2
ho
k1
h1
z
r
𝑞𝜃∨𝜃=360 °
𝑞𝜃∨𝜃=0 °
𝑞𝑧∨𝑧=𝐿𝑞𝑧∨𝑧=0 °
𝑞𝑟∨𝑟=𝑟+Δ 𝑟
𝑞𝑧 𝑟∨𝑟=𝑟
I. Konduksi
• Neraca Kesetimbangan
+ =0
• Penjabaran
• Maka + =0
.............x .............x
.......(1) Jadi:
.................(2)
• Boundary Condition
o MencariSaat
To
T1
T2Tu
r1
r2
ho
k1
h1
Maka
Konduksi dari
To
T1
T2Tu
DEA
There is a fluid between 2 long parallel vertical plates. The right plate is at rest, while the left is moving upward or downward at a constant velocity, vs. Therefore, the system generates shear-driven flow. Assume flow is laminar and the fluid is affected by gravity force. No pressure difference is imposed. The distance between 2 plates is B, the width of the plates is W and the length is very long. The fluid is a glycerine solution 30% with density 1000 kg/m3 and viscosity 3 cPoise. B is 0.01 m. Obtain velocity distribution equations for 2 cases, vs = +0.1 m/s and -0.1 m/s,. Plot v against x and shear stress vs x.
SOAL 2
KONDISI 1
SLIDE MANGGALA
Plot Vy vs xx Vy
0 1
1 1613571
2 6487141
3 14620711
4 26014281
5 40667851
0 1 2 3 4 5 60
5000000
10000000
15000000
20000000
25000000
30000000
35000000
40000000
45000000
Vy vs x
Vy
Plot τxy vs x
x τxy
0 49.3
1 -9750.7
2 -19550.7
3 -29350.7
4 -39150.7
5 -48950.7
0 1 2 3 4 5 6
-60000
-50000
-40000
-30000
-20000
-10000
0
10000
τxy vs x
τxy
KONDISI 2
B)
fluid
-vs
x
y
B
-vs
Shell
x
y
Φ𝑥𝑦∨𝑥=𝑥+∆𝑥
Φ 𝑦𝑦∨𝑦=𝐿
Φ 𝑦𝑦∨𝑦=0
Φ𝑧𝑦∨𝑧=0
Φ𝑧𝑦∨𝑧=𝑊
Φ𝑥𝑦∨𝑥=𝑥
z
L
W
Neraca :
+ ()(W. )+ ) = 0
)(W.L)+ )(
Penjabaran
Maka
Sehingga neracanya menjadi :)(W.L) ) = 0)(W.L) = - )
=
= =
=
Boundary condition
X = 0
X = B 0
= 0 = =
Maka : = = =
Plot Vy vs xx Vy
0 -1
1 -1613601
2 -6487201
3 -14620801
4 -26014401
5 -40668001
0 1 2 3 4 5 6
-45000000
-40000000
-35000000
-30000000
-25000000
-20000000
-15000000
-10000000
-5000000
0
Vy vs x
Vy
Plot τxy vs x
x Vy
0 -1
1 -1613601
2 -6487201
3 -14620801
4 -26014401
5 -40668001
0 1 2 3 4 5 6-10000
0
10000
20000
30000
40000
50000
60000
τxy vs x
τxy