Course Objectives

• To provide concepts of engine components of jet propelled engines which are operated in atmosphere

Learning Outcomes

• Understand the internal flow and external characteristics near the inlets. Starting problems and different modes of operation in supersonic inlets.

• Know the types and working principles of axial compressors and centrifugal compressors its velocity diagrams, blade design and performance characteristics of compressors.

• Understand the types and working methods in combustion chambers. The flame stabilization and flame techniques.

• Understand the flow through nozzle, choking, losses in nozzle, variable area nozzle and thrust vectoring.

Course Syllabus

Module I: INTRODUCTION TO AIRCRAFT PROPULSION (4hrs)

Introduction to propulsion , Fundamental equations, Types of aircraft engines Performance parameters , thrust equation , factors affecting thrust and efficiencies.

Practice: Assembly of an aircraft piston engine and Study of an aircraft piston engine, various components, their functions and operating principles

 Module II: DIFFUSER (5hrs)

Subsonic inlet and Internal flow, Major features of external flow, Relation between minimum area ratio and external deceleration ratio, Supersonic inlets, Starting problem on supersonic inlets, Shock swallowing by area variation, External deceleration, Modes of inlet operation.

 Practice: Velocity and pressure variation in a diffuser using 3DS as well as using apparatus

 Module III: AXIAL COMPRESSOR (5hrs)

Working principle of axial compressor, Elementary theory, Velocity triangles, Degree of reaction, Three dimensional flow, Compressor blade design & stage performance calculation, Factors affecting stage pressure ratio , off design performance, Axial compressor performance characteristics.

 Practice: Assembly of an aircraft jet engine compressor

 Module IV: CENTRIFUGAL COMPRESSOR (4hrs)

Working principle of centrifugal compressor, Work done and pressure rise, Inducer and impellor, Velocity diagrams, Compressor stage design, Concept of pre, whirl,  Rotation stall, Centrifugal compressor performance characteristics.

Practice: Cascade testing of a model of axial compressor blade row

Module V: COMBUSTION CHAMBERS  (4hrs)

Classification of combustion chambers, Important factors affecting combustion chamber design, Combustion process, Combustion chamber performance, Effect of operating variables on performance, Flame tube cooling, Flame stabilization, Use of flame holders, Numerical problems.

 Practice: Determination of heat of combustion of aviation fuel

 Module VI: NOZZLES (5hrs)

Theory of flow in isentropic nozzles, Convergent nozzles and nozzle choking, Nozzle throat conditions, Nozzle efficiency, Losses in nozzles, Over expanded , under expanded nozzles , Ejector and variable area nozzles

Practice: Velocity and pressure variation in a high speed nozzel using 3DS

Characteristic plots of a free jet through a non circular and circular orifice using high speed jet

 Module VII:

AFTERBURNER AND  THRUST AUGMENTATION (3hrs)

Working principle of afterburner, afterburner augmentation, Thrust and efficiency

 Text Books:

1. K.Giri Automobile Engineering ,Khanna Publishers 2014

2. Newton and Steeds ‐ Motor Vehicle‐ Illiffee Publisher‐ 2010

Reference Books:

1. Hill,P.G.&Peterson,C.R."Mechanics&ThermodynamicsofPropulsion"Addison‐WesleyLongman INC, 2014

2. V Ganesan, “Gas Turbines”,McGraw‐Hill Education, 2010

3. Mathur,M.L and Sharma,R.P, "Gas Turbine Jet and Rocket Propulsion", Standard Publishers &Distributors,Delhi,2014

Source of reference; NPTl

"https://www.youtube.com/watch?v=Hlj2eVt1Vbk&list=PLbMVogVj5nJQt5nsksLn4qcsBrDL_JKkd"

Session Plan

Session 1

Introduction to propulsion , Fundamental equations

https://www.youtube.com/watch?v=KjiUUJdPGX0&t=29s

thrust_NASA

Session 2

Types of aircraft engines Performance parameter

Engine characteristics

Session 3

factors affecting thrust and efficiencies

Session 4

Practice: Assembly of an aircraft piston engine and Study of an aircraft piston engine, various components, their functions and operating principles

Session 5

Practice: Assembly of an aircraft piston engine and Study of an aircraft piston engine, various components, their functions and operating principles-- continue from above session

Session 6

Subsonic inlet and Internal flow

subsonic_inlet_flow

https://www.youtube.com/watch?v=yHnZBfGA2Rs

Session 7

Major features of external flow, Relation between minimum area ratio and external deceleration ratio

Session 8

Supersonic inlets

upersonic inlet

https://www.youtube.com/watch?v=qj8hNe_JXyM

Session 9

Starting problem on supersonic inlets

Engine inlet

Session 10

Shock swallowing by area variation, External deceleration, Modes of inlet operation

Session 11

Practice: Velocity and pressure variation in a diffuser using 3DS as well as using apparatus

.

Session 12

Practice: Velocity and pressure variation in a diffuser using 3DS as well as using apparatus

Session 13

Working principle of axial compressor

https://www.youtube.com/watch?v=Wh4Furbn1Gk

Axial compressor

Session 14

Elementary theory, Velocity triangles

https://www.youtube.com/watch?v=xVttrk62rpo

Session 15

Degree of reaction, Three dimensional flow

Session 16

Compressor blade design & stage performance calculation

Session 17

Factors affecting stage pressure ratio , off design performance,

Session 18

Axial compressor performance characteristics.

Session 19

Practice: Assembly of an aircraft jet engine compressor blade

Session 20

Practice: Assembly of an aircraft jet engine compressor

Session 21

Working principle of centrifugal compressor

centrifugal compressor

https://www.youtube.com/watch?v=lVsKQVRkODk

Session 22

Work done and pressure rise, Inducer and impellor, Velocity diagrams,

Inducer and impellor

https://www.youtube.com/watch?v=5Engz3ZolYk

Session 23

Compressor stage design, Concept of pre whirl,

centrifugal Compressor stage design

Session 24

Rotation stall, Centrifugal compressor performance characteristics.

https://www.youtube.com/watch?v=6yjEbuc7Hqw

Session 25

Practice: Cascade testing of a model of axial compressor blade row

Session 26

Practice: Cascade testing of a model of axial compressor blade row

Session 27

Classification of combustion chamber of jet engine

Classification of combustion chamber of jet engine

Module 6

https://www.youtube.com/watch?v=QnNFNDjHyqM

Session 28

Important factors affecting combustion chamber design, Combustion process

combustion chamber design

https://www.youtube.com/watch?v=LChODuKJNtI

Session 29

Combustion chamber performance, Effect of operating variables on performance,

Session 30

Flame tube cooling, Flame stabilization, Use of flame holders

Session 31

Theory of flow in isentropic nozzles

Nozzles

Session 32

Convergent nozzles and nozzle choking, Nozzle throat conditions

Convergent nozzles

Session 33

Over expanded , under expanded nozzles

underoverexpanded_two

Session 34

Ejector and variable area nozzles

Ejector and variable area nozzles

https://www.youtube.com/watch?v=jJ7qvhsuWQk

Session 35

Practice: Velocity and pressure variation in a high speed nozzel using 3DS

Session 36

Practice:  Characteristic plots of a free jet through a non circular and circular orifice using high speed jet

Session 37

Working principle of after burner

Afterburner

https://www.youtube.com/watch?v=qyMrh65fVsY&t=79s

https://www.youtube.com/watch?v=vpsifCZJvl4

Session 38

afterburner augmentation

https://www.youtube.com/watch?v=vtkveM6fwXE

Session 39

Thrust and efficiency

Thrust and efficiency

https://www.grc.nasa.gov/WWW/K-12/airplane/turbab.html#:~:text=When%20the%20afterburner%20is%20turned,you%20burn%20much%20more%20fuel.

Session 40

Practice: Velocity and pressure variation in a high speed nozzel using 3DS

Session 41

Practice: Characteristic plots of a free jet through a non circular and circular orifice using high speed jet

Case Studies

Case Studies