The document discusses the basics of internal combustion (IC) engines. It describes IC engines as converting chemical energy from fuel into thermal and then mechanical energy. The working principle involves combustion occurring inside the engine cylinder, where high pressure and temperature gases exert force on the piston. A four stroke engine is then explained as intake, compression, power, and exhaust strokes. Key parts of a four stroke IC engine are also defined, including the piston, crankshaft, connecting rod, flywheel, valves, and spark plug. Applications mentioned are road vehicles, aircraft, and small machines.

1. Basics of IC Engines
by
Rampal Singh
Assistant Professor
Rai University, Ahmedabad
B.E. (Mechanical), M.Tech (Production Engineering),
Thrice GATE Qualified

2. Outline
Heat engines and types
Working principle
Working of four stroke engine
Parts of four stroke engine
Applications

3. Engines
(converts one form of energy into other)
External combustion
engine
(combustion takes place outside)
Internal Combustion
Engine
(combustion takes place inside)

4. Chemical energy
(Fuel)
Thermal Energy
(burning of fuel)
Useful work
(mechanical
energy)
Working Principle

5. Working Principle
• All the process takes place inside engine cylinder
• High P,T gas produced will exert force on piston piston
to convert it into mechanical energy

6. Working of four stroke Engine

8. Parts of four stroke Engine
• Piston
• In an engine, a piston transfers the expanding forces of gas to
mechanical rotation of the crankshaft through a connecting rod.
• Crankshaft
• A crankshaft is a part that converts the reciprocating motion to
rotational motion.
• Connecting Rod
• It transfers motion from a piston to crankshaft acting as a lever arm

9. Parts of four stroke Engine
• Flywheel
• The flywheel is a rotating mechanical device that is used to store
energy.
• Inlet and Outlet Valves
• It allows us to enter fresh air with fuel & to exit the spent air-fuel
mixture from the cylinder.
• Spark Plug
• It is a device that delivers electric current to the combustion chamber
which ignites the air-fuel mixture leading to the abrupt expansion of
gas.

10. Road vehicles (two wheeler, four
wheeler)
Aircrafts
Small machines such as lawn movers,
portable engine generators
Applications of IC Engines