The document provides an overview of internal combustion engines (IC engines), detailing their historical development, fundamental principles, and classifications based on various criteria. It distinguishes between two-stroke and four-stroke engines, along with different types such as petrol and diesel engines, highlighting their distinct operational mechanisms and performance characteristics. Additionally, it describes key components of an IC engine, including the cylinder, piston, crankshaft, and valves, outlining their functions and materials used.

1. 20ME703PE &
ADVANCED IC ENGINES

2. INTERNAL COMBUSTION ENGINES
(IC ENGINES)`

3. INTRODUCTION
Perhaps the invention of the engine, or even introducing its
concept, was the most important scientific event in the
human history.
The revolutionary result was the replacement of the horse
carriage by the automobile or the HORSE-LESS CARRIAGE,
as it was initially called.
Engines are basic mechanical engineering devices, and they
have variety of applications in moving and non-moving
machines

4. NIKOLAS OTTO (1876)
History of I.C. Engine The internal combustion engine was first conceived and
developed in the late 1800’s•The man who is considered the inventor of the
modern IC engine and the founder of the industry is pictured to the TOP….Nikolas
Otto (1832-1891).•Otto developed a four-stroke engine in 1876, most often
referred to as a Spark Ignition, since a spark is needed to ignite the fuel air
mixture.

5. WHAT IS AN ENGINE’?
Engine is a device that converts heat
energy into mechanical energy
Heat energy is obtained
by
combustion of fuel

6. The combustion may take place
within the
engine cylinder
outside the
engine cylinder
Internal Combustion Engine
– IC Engine
External Combustion Engine
– EC Engine

7. Spark Ignition Compression
Ignition
Spark Ignition Engine
– SI Engine
(Otto / Gasoline Engines
Compression Ignition Engine
–CI Engine
(Diesel Engines)
The combustion may be induced by

8. CLASSIFICATION OF I.C.ENGINES
1. Number of Strokes
2. Fuel use
3. Working Cycle
4. Engine Design or
Cylinder arrangements
5. Fuel Supply
6. Method of Ignition
7. Basic Engine Design
8. Method of governing
9. Speed
10. Cooling system
11. Valve location
12. Lubrication
13. Application

9. CLASSIFICATION OF I.C.ENGINES
1. Number of Strokes
2. Fuel use
3. Working Cycle
a)Two Stroke
b) Four Stroke
a) Petrol or Gasoline Engine
b) Diesel Engine
c) Gas Engine
d) Dual Fuel Engine
a) Otto Cycle
b) Diesel Cycle
c) Dual combustion Cycle

10. CLASSIFICATION OF I.C.ENGINES
4. Engine Design or Cylinder arrangements
5. Fuel Supply
6. Method of Ignition
a) Inline Engine
b) V Engine
c) Radial Engine
d) Opposed Cylinder Engine
e) Vertical engine
f) Horizontal Engine
a) Carbureted Type
b) Injection Type
a) Spark Ignition
b) Compression Ignition

11. CLASSIFICATION OF I.C.ENGINES
7. Basic Engine Design
8. Method of governing
9. Speed
a) Quality Governed Engine
b) Rotary Engine
a) Quality Governed Engine
b) Quantity Governed Engine
c) Hit & Miss Governed Engine
a) Low Speed Engine
b) High Speed Engine
c) Medium Speed Engine

12. CLASSIFICATION OF I.C.ENGINES
10. Cooling system
11. Valve location
12. Lubrication
a) Air Cooled Engine
b) Water Cooled Engine
a) Overhead Valve Engine
b) Side valve Engine
a) Wet sump lubrication Engine
b) Dry Sump Lubrication Engine

13. CLASSIFICATION OF I.C.ENGINES
13. Application
a) Stationary Engine – Pump sets, Gensets,
Mills etc.,
b) Marine Engine – Ship. Outboard, Inboard etc.,
c) Locomotive Engine – Earth movers, Snow
Movers, Tractors, Tippers, Dumpers etc.,
d) Automotive Engine – Car, Bus, Trucks etc.,
e) Aircraft Engine – Civil Aircrafts, War air Crafts
etc.,

17. MAJOR PARTS OF AN I.C. ENGINE
1. Cylinder
2. Cylinder Head
3. Piston
4. Piston rings
5. Connecting rod
6. Crank shaft
7. Cam shaft
8. Crank case
9. Fly wheel
10.Valves
11.Water jackets

18. CYLINDER
Cylinder: A round cylindrical casting in which a piston slides in and out to make
stroke. The cylinder is closed by a cylinder head.
Material: Grey Cast Iron, Aluminum

19. HEAD
Cylinder Head: It is fitted at the top of the cylinder. T as inlet and outlet
valves, spark plug/Fuel Injector, Water jackets

20. PISTON
Piston: It is a device which transmits energy to the connecting rod. It slides
up and down inside the cylinder. It has three grooves to accommodate

21. PISTON RINGS
Piston rings: Piston rings are inserted in the grooves of piston.
1). Oil ring: One ring is used
2). Compression Rings: Two rings are used
Material: Alloy cast iron plated with chromium or cadmium

22. CONNECTING ROD
Connecting rod: It converts the reciprocating motion of the piston into rotary
motion of the crank shaft. The small end of the connecting rod is
connected to piston and the big end to the crank shaft
Material: Plain carbon steel, Aluminum alloys, Nickel alloy, Steel

23. CRANK SHAFT
Crank shaft: The device used for getting power from the motion of the
piston and connecting rod and this power is applied to the flywheel
Material: Alloy steel, SG Iron

24. FLY WHEEL
9. Fly wheel: It is a big wheel attached with crank shaft. It maintains the
speed of the engine.

25. CAM SHAFT
7. Cam shaft: It operates the opening and closing of the engine valves. It
has number of cams which are driven by crank shaft through timing
gears. The function of the cam is to convert the rotary motion into linear
reciprocating motion

26. VALVES
Valves: The function of the valve is to admit fresh charge in the cylinder and to
send the discharge gases out. There are two valves namely inlet valve and
outlet valve.
Material
Inlet Valve: Nickel Chrome, Chrome molybdenum
Outlet Valve: Nickel Chrome, Stainless Steel, Tungsten Steel, Silicon chrome
steel

27. WATER JACKETS
1. Water jackets: Provided in the cylinder head. Purpose of the water
jackets is to keep the walls of the engine cool.

28. FOUR STROKE ENGINE
In a four stroke engine, one power stroke is
completed for every four strokes of the piston
or during two revolutions of the crankshaft
Petrol Engine: It is also known as Spark
Ignition (SI) Engine.
Four stroke Petrol requires four strokes of the
piston for one cycle of operation
The four strokes are:
1. Suction stroke 2. Compression stroke
3. Expansion stroke 4. Exhaust stroke

30. 4 STROKES OF THE IC ENGINE

31. TWO STROKE ENGINE
In the two stroke engine, the cycle of operation
is completed in two strokes of the piston or one
revolution of the crankshaft .
The charging of the cylinder with air-fuel
mixture (or air) is done by the following two
methods.

32. TWO STROKE ENGINE
1.Closed Crank compression: The piston
movement is caused by air in the crank case.
So the compressed air admitted into the
cylinder
2.Separate pump method: The charged air or
the air-fuel mixture is compressed by a
separate pump and the pump is driven by the
engine itself.
This method is used in multi cylinder engines

36. TWO STROKE PETROL ENGINE

37. WORKING PRINCIPLE OF TWO STROKE
PETROL ENGINE
In two stroke engine, one power stroke is
completed for every two strokes of the
piston or one revolution of the crankshaft
A two stroke engine has no valves and only
ports are present. There are three ports
namely inlet port, exhaust port and transfer
ports.

38. WORKING PRINCIPLE OF TWO STROKE
PETROL ENGINE
The strokes are:
1.First stroke – compression, suction and
ignition
2.Second stroke – Expansion and exhaustion

39. DIESEL ENGINE
OR
COMPRESSION IGNITION ENGINE
(C.I. ENGINE)

40. WORKING PRINCIPLE OF DIESEL
ENGINE
The working is similar to that of a petrol
engine and the only difference is a fuel injector
is present instead of a spark plug.
This is known as “Diesel Cycle”

41. WORKING PRINCIPLE OF FOUR STROKE
DIESEL ENGINE
1.Suction Stroke
2.Compression Stroke
3.Power or Working Stroke of Expansion stroke
4.Exhaust Stroke

42. FOUR STROKE DIESEL
ENGINE

43. WORKING PRINCIPLE OF TWO STROKE
DIESEL ENGINE
1.First Stroke - Compression and Ignition
(Upward movement of Piston)
2.Second Stroke – Expansion and Exhaust
(Down Ward movement of Piston)

44. TWO STROKE DIESEL ENGINE

45. DIFFERENCE BETWEEN TWO STROKE AND
FOUR STROKES CYCLE ENGINE
Sl.
No
Four Stroke Engine Two Stroke Engine
1
One Power stroke is
obtained in two
rotations of the
crankshaft
One Power stroke is
obtained in each
rotation of the
crankshaft
2 Valves are provided Ports are provided
3
The engine is cooled by
water
The engine is cooled by
air
4 More space required Less space required

46. DIFFERENCE BETWEEN TWO STROKE AND
FOUR STROKES CYCLE ENGINE
Sl.
No
Four Stroke Engine Two Stroke Engine
5
Heavier fly wheel
required
Lighter fly wheel
required
6
Thermal efficiency is
more
Thermal efficiency is
less
7
Volumetric efficiency is
more
Volumetric efficiency is
less
8 Less fuel consumption More fuel consumption

47. DIFFERENCE BETWEEN TWO STROKE AND
FOUR STROKES CYCLE ENGINE
Sl.
No
Four Stroke Engine Two Stroke Engine
9
Requires more
lubrication
Requires less
lubrication
10 Torque is not uniform Torque is uniform
11
Heavier Engine
Ex: Car, Bus, Aeroplane
Lighter Engine
Ex: Scooters, Mopeds

48. DIFFERENCE BETWEEN PETROL ENGINE AND
DIESEL ENGINE
Sl.
No
Petrol Engine Diesel Engine
1
Operates on the
principle of Otto Cycle
Operates on the
principle of Diesel Cycle
2
Fuel is ignited by spark
plug
Fuel is ignited by hot
compressed air
3
Less compression ratio
(6 to 8)
High compression ratio
(15 to 20)
4 Operates at high speed Low speed
5
Fuel used is petrol and
costly
Fuel used is diesel and
cost is less

49. DIFFERENCE BETWEEN PETROL ENGINE AND
DIESEL ENGINE
Sl.
No
Petrol Engine Diesel Engine
6 Lighter in weight Heavier in weight
7
Fuel is sent to cylinder
through carburetor
Fuel is sent through
fuel injector
8
Fuel consumption is
more
Fuel consumption is
less
9 Less Vibration More Vibration
10
Petrol is more volatile.
So, handling is more
risky
Diesel is less volatile.
So, handling is not risky

50. Thank You