1. MEL713 – DESIGN OF I.C. ENGINES: COMPONENTS & SUB-SYSTEMS
J P Subrahmanyam
Professor
Mechanical Engineering Department
IIT Delhi
A Pure Passion, Lead to Most Essential Technology…..

2. A Dream Machine… To search for a better horse.
Motive Power as much as we need and Whenever we need…..
The automobile as we know it was not invented in a single day by a single inventor.
The history of the automobile reflects an evolution that took place worldwide.
It is estimated that over 100,000 patents created the modern automobile.
A simple anatomy creates a versatile environment to convert chemical energy of fuel into Mechanical Motive Power.

3. A Simple Anatomy A cylinder A Piston A Connecting Rod A Crank
Convert fuel energy to Most active mobile power.
What led to the invention of Piston & Cylinder?
The effect of 130 years of evolution!?!?!

4. Evolution of Efficiency of The Dream Machine
A Characteristic of An Intellectual Animal ???

8. Course Objectives The objective of the course is :
To introduce advanced concepts of the various aspects.
To discuss and analyze the processes of the I.C. engine.
The student will be exposed to:
various design features and operating characteristics of the engine,
its components and its sub-systems.

9. Daily Routine
Inhalation of fresh air.
Intake of diet.
Compression of air.
Digestion of intake with air.
Generation of Mechanical Motion.
Exhalation of waste.
A cyclic creature called natural air breathing Machine.
Actions are discrete but final outcome is continuous.

10. Strategies for Execution of Routine
Sequence of Events.
Duration of events.
Pace of realization of an event.
Magnitude of each event.
This leads to classification of IC engines.

11. Engine Classifications
Cycle (2- vs. 4-stroke)
Valve vs. Port (OH Cam, etc.)
Fuel (Gasoline, NG, diesel)
Fuel/Air Mixing (carburetor, fuel injection)
Ignition (spark, compression)
Load Control (fuel control, air/mixture control)
Cooling (direct air, indirect air, un-cooled)
Application (road, RR, marine, airborne, utility, stationary)
Design (rotary, reciprocating)

14. Major operation Strategy
Efficient Space Management: 4-stroke cycle: Requires two complete revolutions to complete a cycle
Efficient Time Management: 2-stroke cycle: Requires one complete revolution to complete a cycle

17. 1 4 3 2

18. Wastage of Space
(Wastage of Time)

19. The instantaneous active cylinder volume is a strong function of angular displacement of crank angle.
The p-V diagrams can be easily translated into p-q diagram.
P-q diagram gives a true picture of engine operation.

20. Cold Period of Operation
Hot Period of Operation

21. Co-ordination of Valve Action with Piston Displacement