Aerodynamics of Compressors and Turbines · 2015. 7. 6. · Aerodynamic Principles 12 • Perfect gas/air, Ideal fluid – Isentropic – adiabatic, irreversible fluid flow process

Aerodynamics of

Compressors and Turbines(AE 651)

Autumn Semester 2009

Instructor : Bhaskar RoyProfessor, Aerospace Engineering Department I.I.T., Bombaye-mail : [email protected]

AE 651

Elective Course : Ph.D / M.Tech / D.D / B.Tech

The coverage in this course will be with reference to their application in Aerospace engineering and specifically with reference to Compressors and Turbines as used in Aircraft Gas Turbine engines. They are also relevant to Compressors and Turbines used in land based thermal power generation power plants .

AE 651- Prof Bhaskar Roy, IITB Lect - 1

Coverage

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1. Axial Flow Compressors2. Centrifugal Flow Compressors3. Axial Flow Turbines4. Radial Flow Turbines5. Matching of Compressors & Turbines6. Mathematical models for 3-D flow in

turbomachinery7. CFD methods for flow analysis in

compressors and turbines

AE 651- Prof Bhaskar Roy, IITB Lect-1

References

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1. Hill Philip, Peterson Carl, Mechanics and Thermodynamics of Propulsion, 2nd Edn., Addison Wesly, 1992.

2. El-Sayeed G Ahmed, Aircraft Propulsion and gas Turbine Engines, CRC press, 2008.

3. Saravanamuttoo, H.I.H., Rogers G.F.C., Cohen H. Gas Turbine Theory, 5th Edition, Pearson, 2001.

4. Bhaskar Roy, Aircraft Propulsion, Elsevier, 2008


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CDEEPDate-wise schedule : Course Details

AE 651Aerodynamics of Compressors

and Turbines

Prof. Bhaskar Roy

AE 651- Prof Bhaskar Roy, IITB Lect - 1

Course Details – AE 651

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No. Date Lecture /. TopicTutorial No

1. 23.07.09 Lect-1 Course Coverage, Introduction to AerodynamicMachines

2. 27.07.09 Lect-2 Ch-1, Introduction to Axial Flow Compressors3. 30.07.09 Lect-3 Ch-1, Thermodynamics of Axial Flow

Compressor4. 03.08.09 Lect- 4 Ch-1, 2-D cascade flow theory of Axial Flow

Compressor5. 06.08.09 Tute-1 Quiz and Assignment - Aerothermodynamics of

Axial Flow Compressor6. 10.08.09 Lect-5 Ch-1, 3-D flows in AFC –Vortex theories7. 13.08.09 Lect-6 Ch-1, Losses and Efficiencies of AFC8. 17.08.09 Tute-2 Quiz and Assignment - 3-D flows and efficiencies9. 20.08.09 Lect-7 Ch-1, Characteristics of Single and Multi-stage

Compressors10. 24.08.09 Lect-8 Ch-1, Aerodynamic design of Axial Flow

Compressor


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11. 27.08.09 Lect-9 Ch-2, Aerodynamics of Centrifugal Compressors12. 31.08.09 Lect-10 Ch-2, Characteristics of Centrifugal Compressors14. 03.09.09 Tute-3 Quiz and assignment on Centrifugal Compressor.

15. 17.09.09 Lect-11 Ch-3, Introduction and 2-D theories of Axial Flow Turbine

16. 24.09.09 Lect-12 Ch-3, Thermodynamics, Losses & Efficiencies of AFT

17. 01.10.09 Lect-13 Ch-3, Characteristics of Single & Multi-stage AFT18. 05.10.09 Tute-4 Quiz and Assignments on Axial Flow Turbines19. 08.10.09 Lect-14 Ch3, Cooling Techniques used in AFT20. 12.08.09 Lect-15 Ch3, Aerodynamics Design of AFT


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21. 15.10.09 Lect-16 Ch 4, Aerodynamics of Radial Flow Turbines22. 22.10.09 Tute- 5 Quiz and Assignment on RFT23. 26.10.09 Lect-17 Ch-5, Matching of Compressors and Turbines24. 29.10.09 Lect-18 Ch-6, Aerodynamic Analysis of Compressors

& Turbines – 3-D flow theories25. 05.11.09 Lect-19 Ch-6,Aerodynamic Analysis of Compressors &

Turbines – Radial Equilibrium Equation and Streamline Curvature Theories.

26. 09.11.09 Lect-20 Ch-7,Computational Techniques and CFD tools27. 12.11.09 Lect-21 Ch-7, Examples of CFD analysis of Compressor

and Turbine flows

Gas Turbine Engine

7AE 651- Prof Bhaskar Roy, IITB Lect-1

LPCompressor

Fan LP Compressor

HP Compressor

HPTurbine

LP Turbine

Inner Shaftcarrying LPT,LPC and Fan

Outer shaftcarryingHPT and HPC

HotJet

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Aerodynamic Machines• All the above machines work on

various Aerodynamic principles and laws

• They also have to conform to various Laws of Motion (e.g. Newton’s laws)

• All these machines also need to conform to laws of thermodynamics, especially when they are part of a heat engine e.g. Gas Turbine Engine for aircraft propulsion


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Laws of Motion• 1st Law of Motion – Concept of

applying energy or force on fluid flow• 2nd Law of Motion – Concept of

acceleration (or deceleration) of fluid • 3rd Law of motion – Concept of

Reaction force due to application of a force, due to acceleration


Laws of Thermodynamics

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• 1st Law of Thermodynamics – Equality of supplied energy and work done – brings in the concept of Cycle - in flowing fluid

• 2nd Law of Thermodynamics – Concept of Entropy, and change of entropy, ∆s

• 3rd Law of Thermodynamics – Concept of absolute zero temperature (Temp in K)

• Concept of Static and Stagnation (Total) Pressure (p , p0) and Temperature (T, T0)

• Equation of state p = ρRT assumed valid


Aerodynamic Laws

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• Newtonian fluid – continuum theory is valid• Conservation of mass in a fluid flow –

Continuity equation• Conservation of momentum in a fluid flow –

Euler’s equation• Conservation of energy in a fluid flow –

Bernoulli’s equation – incompressible flow and ideal fluid p0 = p + 1/2.ρ. V2

Navier-Stoke’s equation – real fluid for both incompressible and compressible flows


Aerodynamic Principles

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• Perfect gas/air, Ideal fluid – Isentropic – adiabatic, irreversible fluid flow process

• Effects of Mach number, Reynolds number etc. shall be made liberally

• More parameters for dynamical similarity shall be developed for compressors / turbines

• Incompressible and Compressible fluid flow• Subsonic and Supersonic flows – shock theories –

2-D planar shocks and property changes across the shocks

AE 651- Prof Bhaskar Roy, IIT B Lect-1

Pre-requisites

Some prior knowledge of all the above subjects is a pre-requisite for this course

AE 651- Prof Bhaskar Roy, IIT B Lect-113

Working of Compressors and Turbines

• Compressors perform work on the passing air. Work is done on the air often with the help of airfoil shapes

• Turbine extract workfrom the passing air often with the help of airfoil shapes

Lift

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Drag


Highly CamberedBlade section forTurbines

Employing AirfoilsCompressor Airfoils Turbine Airfoil

T- 6 blade section

15AE 651- Prof Bhaskar Roy, IIT, B Lect-1

Employing Airfoils

a) Normal b) Excessive turning c) Excessive Stagger

Diffusing Flow in Axial Compressor Passages

16Lect-1AE 651- Prof Bhaskar Roy, IITB

Employing Airfoils

Accelerating Flow in a Turbine Passage

17AE 651- Prof Bhaskar Roy, IITB Lect-1

Documents

Aerodynamics of Compressors and Turbines · 2015. 7. 6. · Aerodynamic Principles 12 • Perfect gas/air, Ideal fluid – Isentropic – adiabatic, irreversible fluid flow process