The document provides an overview of internal combustion (IC) engines, including their classification based on thermodynamic cycles, fuel type, ignition type, and other characteristics. It details the working principles of 4-stroke and 2-stroke petrol and diesel engines, along with their respective advantages and disadvantages. The content is structured to explain the components and operational differences between various engine types.

1. Presented by-
SHARATH S
01JST16PAE013

2. CONTENTS
 Classification of Heat Engine
 Definition of an IC engine
 Classification of an IC engine
 Components of an IC engine
 4-stroke and 2-stroke petrol engine working principle
 4-stroke and 2-stroke diesel engine working principle
 Difference between 4 & 2 stroke engine
 Difference between petrol and diesel engine

3. Heat Engine
Internal Combustion
Engine (IC Engine)
External Combustion
Engine (EC Engine)

4. Internal Combustion Engine (IC Engine)
An IC Engine is a heat engine in which the combustion of
a fuel (normally a fossil fuel Eg; Petrol, Diesel, LPG etc) occurs with
in a combustion chamber (Engine cylinder).

5. The internal combustion engines (IC Engines) are classified
depending upon
 Nature of Thermodynamic Cycle
 Type of Fuel
 Number of Strokes
 Type of Ignition
 Number of Cylinders
 Position of the Cylinder
 Type of Cooling
Classification of IC Engines

6. The internal combustion engines (IC Engines) are classified
depending upon
 Nature of Thermodynamic Cycle
i. Otto Cycle Engine
ii. Diesel Cycle Engine
iii. Dual Combustion Cycle Engine
Classification of IC Engines

7. The internal combustion engines (IC Engines) are classified
depending upon
 Type of Fuel
i. Petrol Engine
ii. Diesel Engine
iii. Gas Engine ( CNG or LPG or biogas or Hydrogen etc)
 Number of Strokes
i. 2 – Stroke Engines
ii. 4 – Stroke Engines
Classification of IC Engines

8. The internal combustion engines (IC Engines) are classified
depending upon
 Type of Ignition
i. Spark Ignition (SI Engine)
ii. Compression Ignition (CI Engine)
 Number of Cylinders
i. Single Cylinder
ii. Multi-cylinder
Classification of IC Engines

9. The internal combustion engines (IC Engines) are classified
depending upon
 Position of the Cylinder
i. Horizontal Engine
ii. Vertical Engine
iii. Radial Engine
iv. V – Engine
v. Opposite Cylinder Engine
 Type of Cooling
i. Air-Cooled Engine
ii. Water Cooled Engine
Classification of IC Engines

10. Components of an IC Engine

12. 4 – Stroke Petrol Engine Working Principle

13. 2 – Stroke Petrol Engine Working Principle

14. 4 – Stroke Diesel Engine Working Principle

15. 2 – Stroke Diesel Engine Working Principle

16. Difference between 4 & 2-stroke Engine

17. Petrol Engines:
 Advantages
 Relatively clear exhaust
 Low maintenance cost
 Less engine vibration
 Disadvantages
 Poor engine efficiency
 Lower compression ratio
Diesel Engines:
 Advantages
 Higher compression ratio
 Greater efficiency
 Low running cost
 Disadvantages
 Increased NOx emissions due to higher combustion temperatures
 Increased UHC emissions due to incomplete combustion
Advantages & Disadvantages of Petrol and Diesel
Engine