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Course on Internal Combustion Engine (ICE) for Mechanical Engineering Semester - VI
Course on
Internal Combustion Engine (ICE)
for
Mechanical Engineering
Semester - VI
Term Work Evaluation
Term Work:
• Term work shall consist of minimum 08 experiments,
assignments and written test.
• The distribution of marks for term work shall be as
follows:
Laboratory work (experiments/assignments): ...... (15)
Marks.
Test (at least one): ............... (10) Marks.
Practical Examination:................. (25) Marks.
• TOTAL: ..................... (50) Marks.
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Experiments and Assignments
List of Experiments:
1) Study of carburetor.
2) Study of ignition system.
3) Study of fuel injection system.
4) Morse Test on petrol engine.
5) Speed Test on petrol or/and diesel engine.
6) Load Test on diesel engine (engines).
7) Heat Balance test on diesel or petrol engines.
8) Experimental determination of Air fuel ratio.
9) Exhaust Gas/Smoke analysis of S.I./ C.I. engines
10) Effect of Supercharging on Performance Characteristics of an engine
Practical Examination:
• Practical examination of 2 hours duration based on the laboratory experiments.
• Viva-.voce can be conducted during practical examination. 1/29/2014 Prof. Irfan Shaikh 3
Text and References
Text Books:
1. Internal Combustion Engine - Mathur and Sharma
2. Internal Combustion Engine - E.F. Oberi.
3. Internal Combustion Engine - Domkundwar
4. Internal Combustion Engine - V. Ganesan - TataMcGraw Hill
References:
1.Internal Combustion Engines - Richard Stone - Palgrave Publication
2. Internal Combustion Engine - S.L. Beohar
3. Internal Combustion Engine - Gills and Smith.
4. Internal Combustion Engine - P.M Heldt.
5. Power Plant Engineering - Morse
6. Internal Combustion Engines - V.L. Maleeve
7. Internal Combustion Engines - Taylor.
8. Internal Combustion Engines Fundamentals - John B. Heywood
9. Internal Combustion Engines S.S.Thipse,JAICO.
10. Internal Combustion Engines Willard w.pulkrabek, Pearson Education.
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Course Content
• Construction features and types of IC Engines
• Two stroke and Four stroke engines
• Actual and Ideal cycle analysis
• Carburetion theory and analysis
• Ignition and Injection system analysis
• Combustion phenomena of S.I and C.I Engines
• Fuel injection system for S.I and C.I Engines
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Module - 1
Module - 1
• Construction features of Reciprocating IC Engines
• Types of Combustion Engines
• Two stroke and Four stroke engines
• Comparative study of 2S and 4S Engines
• Ideal cycle analysis viz. Otto, Diesel, Dual cycle
analysis
• Fuel-Air cycle analysis and its effects on
performance parameter
• I.C Engine performance parameters
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Diagram of energy conversion in an
internal combustion engine or gas
turbine
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A typical cut view of IC Engine
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Classification of IC Engine
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Classification based on Cylinder
arrangement
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Applications of Engines
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Cross-section of four-stroke cycle S1 engine showing engine components;
(A) block, (B) camshaft, (C) combustion chamber, (D) connecting rod, (E)
crankcase, (F) crankshaft, (G) cylinder, (H) exhaust manifold, (I) head, (J) intake
manifold, (K) oil pan, (L) piston, (M) piston rings, (N) push rod, (0) spark plug, (P)
valve, (Q) water jacket.
Components of I.C Engine
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Components of I.C Engine
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Cylinder Block with Valve train
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FOUR STROKE ENGINE
OPERATION
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FOUR STROKE ENGINE
OPERATION
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Compression ratio
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Working of 2-Stroke Engine
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Comparative study of 4-S and 2-S
I.C Engine• Cycle completes in 4-S
• Turning moment is not uniform
• One power stroke in every two revolution
• Power to weight density is less
• Lower rate of wear and tear
• Less cooling is required
• Valve arrangement for charge flow
• Initial cost is more
• Volumetric efficiency is more
• Thermal efficiency is higher
• Used where efficiency is important viz., cars, buses, truck etc.
• Cycle completes in 2-S
• Turning moment is uniform
• One power stroke in each revolution
• Power to weight density is more
• Higher rate of wear and tear
• More cooling is required
• Valveless (Ports) arrangement for charge flow
• Initial cost is less
• Volumetric efficiency is less
• Thermal efficiency is lower
• Used where low cost, compactness and light weight are important viz., mopeds, scooters, motorcycles etc.
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Piston cylinder crankshaft
arrangement on I.C Engine
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Piston components of I.C Engine
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Piston and Connecting Rod
Assembly of I.C Engine
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Cutaway of an engine showing the
cylinder, piston, connecting rod, and
crankshaft.
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Actual Indicator diagram on I.C
Engine
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Brake Power and Engine Torque
Characteristics of I.C Engine
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Properties or Characteristics of
Thermodynamics
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Ideal Cycle Analysis (Otto Cycle)
p-v Diagram
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Thermal efficiency vs. Compression ratio
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Ideal Diesel Cycle Analysis
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The dual combustion cycle
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Comparison of Otto, Dual, Diesel cycle
based on performance parameter
( TIt)OTTO > (TIt )DUAL > (TIt )DIESEL
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Comparison contd..
( TIt )DIESEL > (TIt )DUAL > (TIt )OTTO
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Fuel-Air Cycles
• The simple ideal air standard cycles
overestimate the engine efficiency by a
factor of about 2.
• A significant simplification in the air
standard cycles is the assumption of
constant specific heat capacities.
• Heat capacities of gases are strongly
temperature-dependent,
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Variation of efficiency with equivalence ratio
for a constant-volume fuel-air cycle with 1 -
octane fuel for different compression ratios
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Variation of efficiency with compression ratio for a constant-volume
fuel-air cycle with 1 -octene fuel for different equivalence ratios
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Actual Engine or Fuel-Air Cycles• Real engines operate on an open cycle with changing composition.
• There is a loss of mass during the cycle due to crevice flow and blowby past
the pistons.
• In a real engine inlet flow may be all air, or it may be air mixed with up to 7%
fuel.
• Specific heats of a gas have a fairly strong dependency on temperature and
can vary as much as 30% in the temperature range of an engine (for air, cp =
1.004 kJ/kg-K at 300 K and cp = 1.292 kJ/kg-K at 3000 K ).
• Heat loss during combustion lowers actual peak temperature and pressure
from what is predicted. The actual power stroke, therefore, starts at a lower
pressure, and work output during expansion is decreased.
• SI engines will generally have a combustion efficiency of about 95%, while CI
engines are generally about 98% efficient.
• SI engine is always somewhat less than what air-standard Otto cycle analysis
predicts. This is caused by the heat losses,. friction, ignition timing, valve
timing, finite time of combustion and blowdown, and deviation from ideal gas
behavior of the real engine.1/29/2014 Prof. Irfan Shaikh 42
