1. Alternatives of IC engine
 Muhammad Ishtiaq Khan 19PWMEC4830
 Muhammad Salman Khan 19PWMEC4811
 Hazrat Ali 19PWMEC4775
 Muhammad Bilal 19PWMEC4714

2. What is IC engine
 In internal combustion (IC) engine, the combustion of fuel takes place
inside the engine cylinder and heat is generated within the cylinder.
 IC engines are of two types:
1. Reciprocating engine
Examples: Gasoline and diesel engines.
2. Rotary engine
Examples: Wankel engine and open cycle gas turbine
 IC engines are the most common form of heat engines used in
vehicles, boats, ships, airplanes, and trains etc.

3. Alternative of IC engine

4. 1. Wankel Engine

5. Main parts of Wankel engine
 Rotor
 Housing
 Eccentric Shaft/Output Shaft

6. Rotary Design

7. Rotor

8. Continued…
 The rotor has a set of internal gear teeth.
 These teeth mate with a gear that is fixed to the
housing.
 This gear mating determines the path and
direction the rotor takes through the housing.

9. Housing
It is roughly oval in
shape.
The shape of
combustion chamber
is designed so that
three tips of the rotor
will always stay in
contact with the will of
chamber.
Each part of the
housing is dedicated
to one part of the
combustion process.

10. Eccentric Shaft

11. Working

12. Working of Wankel engine

13. Advantages
Much simpler design compare to piston counterpart.
High power to weight ratio.
Less vibration compare to reciprocating type.
Smooth power flow and high RPM

14. Disadvantages
It consumes a lot of fuel.
The spare parts are very costly.
There is incomplete combustion of the air-fuel mixture.
High manufacturing cost.
The rotor apex points are in direct contact with the casing Due
to direct contact cracking is produced.

15. Applications
Automobiles
High-speed boats
Light plane
Helicopters
Snowmobiles

16. 2. Gas Turbine Engine
Gas turbines are a type of internal combustion (IC)
engine in which burning of an air-fuel mixture produces
hot gases that spins a turbine to produce power.
Also called combustion Turbine.
The pressurized gas is created by the burning of a fuel.

17. Main Parts
Intake
Compressor
 Combustion Chamber
Turbine

18. Principle of
Operation
 Intake
Slow down incoming air
Remove distortions
 Compressor
Dynamically Compress air
 Combustor
Heat addition through
chemical reaction
 Turbine
Run the compressor
 Nozzle/ Free Turbine
Generation of thrust
power/shaft power

19. Working Principle
 The basic operation of
the gas turbine is a
Brayton cycle
 Air is compressed to
high pressure by
compressor.
 Then fuel and
compressed air are
mixed in a combustion
chamber and ignited.
 Hot gases are given off
which rotates the
turbine wheel.

20. Efficiency Specific Power Output

21. Methods to increase
Efficiency
Increase pressure ratio
Increase the inlet
temperature
Reheat the working
fluid
Power Output
Reheating the working
fluid.
Increasing the mass
flow inside the
compressor.

22. Uses of Gas turbine
Ships
Locomotives
Helicopter
Tanks

23. 3. Free Piston
Engine
A free-piston engine is a
linear, ”crankless”
internal combustion
engine, in which the
piston motion is not
controlled by a
crankshaft but
determined by the
interaction of forces
from the combustion
chamber gases.

24. Main Parts
Combustion
chamber/cylinder
Bounce cylinder
Spark plug
Carburetor
Gas Turbine

25. Main parts
 Combustion chamber or cylinder- Same as the I C engine a combustion cylinder
is the rigid cylindrical chamber inside which the combustion of air-fuel takes place,
and also it is the housing inside which piston moves.
 Carburetor is a device that mixes air and fuel for internal combustion engines in
an appropriate air–fuel ratio for combustion.
 Bounce cylinder: It is cylinder with a piston which is interconnected with the main
piston. The main function of the bounce cylinder is to stored the energy during
expansion of the F P engine and apply it to starts the compression stroke again for
the working.
 Sparkplug- The spark plug is used to ignite the air-fuel mixture and fuel injector
injectes the diesel fuel during the compression of air which results into the
combustion.
 Loading devices- These are the devices that are used in free piston engine as the
replacement of crankshaft of the IC engine, The selection of the load device which
is to be used depends upon the required application of the F P engine like turbine

26. Working of free piston engine
 The entry of fuel through the inlet port of the engine takes place at the end of expansion
stroke of the engine.
 After the entry of the fuel inlet port closes and the compression of the fuel due to the
compression stroke occurs which in turn increases the pressure of the fuel inside the
combustion chamber.
 After this compression fuel gets ignited either by spark plug (gasoline engine) or by
compression (diesel engine) depending upon the type of the F P engine used.
 Due to this combustion of the fuel high pressure impulse is generated which in turn pushes
the piston and the expansion of the gases produced during the combustion occurs.
 The gases expanded during the expansion stroke are then exhausted with the high pressure
through the exhaust port of the engine during the expansion stroke.
 These exhaust gases having high pressure are blown over the blades of the electric
generator turbine which in turn causes rotation of the turbine and the generation of the
electricity takes place.

27. Working of free piston engine

28. Advantages
Simple design with few moving parts
Low maintenance costs
Less frictional losses

29. Disadvantages
 Poor fuel economy.
 Stability of fuel supply.
 Poor part-load efficiency.
 High combustion rate.
 Reduction gearing is required.

30. Applications
Hydraulic engines, off-highway vehicles
free-piston engine generators, aimed for use
with hybrid electric vehicles