Propulsion

1. Introduction to Turbo Jet Engines,
Working Principle
And
Performance
Prepared By,
Vedprakash Arya

2. Contents
❖Introduction
❖Performance Parameters
❖Working Principle
❖Merits & Demerits

3. Introduction

4. ▪ Turbojets are the oldest kind of general-purpose jet
engines. Turbojets are rotary engines that extracts
energy from a flow of combustion gas.
▪ They produce thrust by increasing the velocity of
the air flowing through the engine and operate on
Newton’s third law of motion " For every action there
is an equal and opposite reaction”.

5. Working Principle

6. ❖Air is drawn into the rotating compressor via the intake and
is compressed to a higher pressure before entering the
combustion chamber.
❖ Fuel is mixed with the compressed air and ignited by a
flame in the eddy of a flame holder.
❖Hot combustion products leaving the combustor expand
through the turbine where power is extracted to drive the
compressor.
❖The gas stream exiting the turbine expands to ambient
pressure via the propelling nozzle, producing a high velocity
jet in the exhaust plume.

10. (
(
Engine Performance Parameters
❖Thrust Equation
❖Efficiency
❖Specific Fuel Consumption

17. E
F
F
I
C
I
E
N
C
Y

19. ❖Very high power-to-weight ratio.
❖Compact than most reciprocating engines of the same power rating.
❖Fewer moving parts than reciprocating engines.
❖Low operating pressures.
❖High operation speeds.
❖Low lubricating oil cost and consumption.
Advantages of Turbojet Engines

20. ❖Cost
❖Longer startup than reciprocating engines.
❖Less responsive to changes in power demand
compared to
reciprocating engines.
Disadvantages of Turbojet Engines

21. Thank
You!