Lecture 1 Im

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Lecture 1

AER 403: Aircraft Engines Design

and Construction

DrDr. Farouk. Farouk OwisOwis

Associate ProfessorAssociate Professor

Cairo UniversityCairo University Faculty ofFaculty of

EngineeringEngineering

Aerospace Dept.Aerospace Dept.

Aircraft Engines Design and

Construction

Instructor: Dr. Farouk Mohamed Owis

[email protected]

Lectures: 3 Hours Weekly on Thursday [8:30-10bi-weekly] & [10:15-11:45 weekly]

Section: 2 Hour Weekly

Text Book: S. Dixon, Fluid Mechanics and

Thermodynamics of Turbomachines, 1998

(Available in the library)

Instructor: Dr. Farouk Mohamed Owis

[email protected]

Lectures: 3 Hours Weekly on Thursday [8:30-10bi-weekly] & [10:15-11:45 weekly]

Section: 2 Hour Weekly

Text Book: S. Dixon, Fluid Mechanics and

Thermodynamics of Turbomachines, 1998



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References

1. N. Cumpsty, Compressor Aerodynamics,

1989 (Available in the library)

2. R. I. Lewis, Turbomachinery Performance

Analysis", 1996 (Available in the library)

3. J.L.Kerrbrock, Aircraft Gas Turbines and

Engines, 19924. P.G.Hill, G.R.Peterson, Mechanics and

Thermodynamics of Propulsion, 1992


References Continued

5. J.D.Mattingly, Elements of Gas Turbine

Propulsion, 2006.

6. H. Cohen, G.C.Rogers, H. Saravanamuttoo,Gas Turbine Theory, 1996


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Course Documents

Lectures, Assignments, ImportantAnnouncements, or other course documentswill be posted on the following web site

www.egypteducation.org

Course key:4304

Everyone is recommended to sign up on thisweb site with his real name in order to haveaccess to the course materials, his grades andreceive e-mails about any possible news.

Course Objectives

To distinguish between the capabilities of

different types of Turbomachines.

To be able to conduct design analysis of

axial flow compressors and turbines.

To be able to predict compressor or

turbine off design performance.


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Knowledge and Understanding

1- Basic knowledge of compressor and turbinecascade characteristics.

2- Stage analysis and effects of its parameters oncompressor and turbine design point

performance.3- Analysis of multistage compressors and turbines.

4- Techniques to Estimate off design performance ofcompressors and turbines.

Course Description

Intended Learning Outcomes of Course

Course Contents Introduction to Gas Turbine Engines (2- lectures)

Types of turbomachiones and non-dimensionalanalysis (1- lect.)

Basic equations (2-lect.)

Introduction to turbomachines (Velocity triangles,2-D cascades) 4-lect.

Axial flow compressor stage analysis

Axial flow compressor Performance

Axial flow turbine analysis

Axial flow turbine performance

3-D flow analysis in turbomachines


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Typical Fighter aircraft Jet Engine

Can you start the design process from here?

Of course no.

We start from broad consideration (concepts)

and increase the level of detail layer after layer.


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Introduction to GasTurbine Engines

Part 1: Classification of gas turbine engines

Part 2: Overall GTE Performance

INTRODUCTION TO GTE

Jet engines are classified into two maincategories:

1- Rocket Engines

Fuel and Oxidizer are carried on the vehicleto reach higher altitudes with better efficiency.There are different categories for the rocketengines depending on the type of thepropellants such as chemical rockets, nuclearrockets and electrical propulsion rockets


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2- Gas Turbine Engines

Fuel only is carried on the vehicle that iswhy they are called air breathing engines.Thus GTE can travel much greaterdistances before refueling. It has alsobetter efficiency than rocket engines but ithas more complicated configurations.

INTRODUCTION TO GTE

Part 1: Classification of gas turbine engines

Turboprop GTE: main propulsive power isobtained by a propeller

High and Low Bypass Turbofan GTE:

Air stream into the engine is divided intoseveral streams to enhance the engineefficiency at lower flight speeds. Propulsivepower is obtained by a single (mixedturbofan engine) or multi jets.

Turbojet GTE: propulsive power is obtainedby the jet


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Schematic diagram of gas generator

Schematic diagram of a turbojet (dual

axial compressor and turbine)


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Types of Gas Turbine Engines (GTE)

2 Spool Turbojet Engine with Afterburner (AB)

In the turbofan, a portion of the turbine work is

used to supply power to the fan. Generally the

turbofan engine is more economical and efficient

than the turbojet engine in the subsonic flight.The thrust specific fuel consumption (TSFC, or

fuel mass flow rate per unit thrust) is lower for

turbofans and indicates a more economical

Turbofan Engines


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2 Stream Turbofan Engine

1 Stream Turbofan Engine with AB


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1 Stream Turbofan Engine -Reversed Flow Combustor

Turbofan EnginesTurbofan EnginesTurbofan Engines

A gas generator that drives a propeller is a

turboprop engine. The expansion of gas through

the turbine supplies the energy required to turnthe propeller. The turboshaft engine is similar to

the turboprop except that power is supplied to a

shaft rather than a propeller. The turboshaft

engine is used quite extensively for supplying

power for helicopters.

Turboprop and Turboshaft

Engines


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Direct Drive Turboprop Engine

Free Turbine Turboprop Engine


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The ramjet engine consists of an inlet, a combustion zone, and a

nozzle. The ramjet does not have the compressor and turbine as the

turbojet does. Air enters the inlet where it is compressed and then

enters the combustion zone where it is mixed with the fuel and

burned. The hot gases are then expelled through the nozzle,

developing thrust. The operation of the ramjet depends on the inlet

to decelerate the incoming air to raise the pressure in the

combustion zone. The pressure rise makes it possible for the

ramjet to operate. The higher the velocity of the incoming air, thegreater the pressure rise. It is for this reason that the ramjet

operates best at high supersonic velocities. At subsonic velocities,

the ramjet is inefficient, and to start the ramjet, air at a relatively

higher velocity must enter the inlet

Ramjet Engine

Schematic diagram of a ramjet