MEL 341 : GAS DYNAMICS

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MEL 341 GAS DYNAMICS JET PROPULSION

• P M V Subbarao
• Professor
• Mechanical Engineering Department

We learn this course as Gas dynamics for Jet
Propulsion
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Course Overview

• This undergraduate level course teaches the
  principles of jet propulsion.
• The primary focus of the course is on the
  teaching of thermodynamics and Gas dynamics in
  aircraft engines.
• The course provides information that will enable
  the engineering analysis of
• ramjets and turbine engines and
• its separate components including inlets,
  nozzles, combustion chambers, compressors, and
  turbines.

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Course Objectives

• Students successfully completing MEL 341 will
  get
• A basic understanding of thermodynamic cycles of
  jet engines.
• A basic understanding of the compressible fluid
  flow in inlets and compressors and turbines.
• A basic understanding of the combustion physics
  in combustion chambers.
• A basic understanding of the rational behind
  several types of jet engines.
• The ability to analyze jet engines determine
  propulsion efficiency and design inlets and
  nozzles.

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Course Contents

• UNIT- I Propulsion
•  Aircraft Propulsion introduction -- Early
  aircraft engines -- Types of aircraft engines --
  Reciprocating internal combustion engines -- Gas
  turbine engines -- Turbo jet engine -- Turbo fan
  engine -- Turbo-prop engine
• Aircraft propulsion theory thrust, thrust power,
  propulsive and overall efficiencies -- Problems.
•  UNIT- II THERMODYNAMIC ANALYSIS OF IDEAL
  PROPULSION CYCLES
•  Thermodynamic analysis of turbojet engine
  Study of subsonic and supersonic engine models --
  Identification and Selection of optimal
  operational parameters. Need for further
  development Analysis of Turbojet with after
  burner.

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• Thermodynamic analysis of turbofan engine Study
  of subsonic and supersonic systems --
  Identification and selection of optimal
  operational parameters. Design of fuel efficient
  engines Mixed flow turbo fan engine Analysis
  of Turbofan with after burner.
• Thermodynamic analysis of turbo-prop engine
  Identification and selection of optimal
  operational parameters.

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UNIT III GAS DYNAMICS OF PASSIVE COMPONENTS OF
TURBO ENGINES

• FUNDAMENTALS OF GAS DYNAMICS Energy equation
  for a non-flow process -- Energy equation for a
  flow process -- The adiabatic energy equation --
  Momentum Equation --Moment of Momentum equation
  -- Stagnation Velocity of Sound --Stagnation
  Pressure -- Stagnation Density -- Stagnation
  State -- Velocity of sound -- Critical states --
  Mach number -- Critical Mach number -- Various
  regions of flow.
• ANALYSIS OF DIFFUSERS AND NOZZLES Introduction
  study of intakes for subsonic and supersonic
  engines -- Comparison of isentropic and adiabatic
  processes -- Mach number variation -- Area ratio
  as function of Mach numbers -- Impulse function
  -- Mass flow rates -- Flow through nozzles --
  Flow through diffusers Effect of friction --
  Analysis of intakes for supersonic engines
  intakes with normal shock oblique shocks
  Study of special supersonic nozzles and
  diffusers.

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UNIT IV STUDY OF COMPRESSORS

• Design and Analysis of compressors
  Classification analysis of centrifugal
  compressors velocity triangles design of
  impellers and diffusers analysis of axial flow
  compressor analysis of stage characterization
  of stage design of multistage axial flow
  compressor Performances analysis of centrifugal
  and axial flow compressors.
•  

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• UNIT V GAS DYNAMICS OF COMBUSTORS
•  Stoichimetry of combustion calculation
  air-fuel ratio gas dynamics of combustors
  thermal loading factors design and selection of
  combustors.
•  UNIT VI STUDY OF TURBINES
• Concept of gas turbine analysis of turbine
  stage velocity triangles and characterization
  of blades and stages Design of multistage axial
  flow turbine Performance analysis of turbines.
•  UNIT VI ADDITIONAL TOPICS
• Thermodynamic analysis real turbo engine cycles
  performance analysis and thermodynamic
  optimization.
•  Introduction to ramjets study of rocket
  engines study of missile engines.

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Books References

• Jet Propulsion
• Flack, R.D.., Fundamentals of Jet Propulsion,
  Cambridge University Press, 2005.
• Baskharone, E.A., Principles of Turbomachinery
  in Air-Breathing Engines, Cambridge University
  Press, 2006.
• Kerrebrock J.L., Aircraft Engines and Gas
  Turbines, MIT Press, 1992.
• Mattingly, J.D., Elements of Gas Turbine
  Propulsion, McGraw-Hill Inc., 1996.
• Gas Dynamics
• Anderson, J.D., Modern Compressible Flow With
  Historical Perspective, McGrawHill, 2002.
• Zuker, R.D., and Biblarz, O.,Fundamentals of Gas
  Dynamics, John Wiley Sons Inc., 2002.
• Thompson, P. A. Compressible Fluid Dynamics.
  Maple Press Company, 1984.
• Saad, M.A.,Compressible Fluid Flow,
  Prentice-Hall, 1993.
• Liepmann, H., and A. Roshko. Elements of Gas
  Dynamics. John Wiley Publishers, 1957.