ADVANCED

PROPULSION
SYSTEMS
AAE 4043
Chapter Topic Learning objectives
1 Introduction Course outline, objectives, introduction to advanced propulsion and
aerothermodynamics, limitations of turbojets and turbofans, Need for supersonic
combustion

2 Ramjet, Scramjet and pulsejet Ramjet engines, working principle, basic consideration, operating principles
Propulsion and performance, basic principle of operation, thrust calculation, efficiency,
inlet types, combustor design, nozzle considerations, Scramjet, spill-over drag,
plume drag. Isolator, combustor, thermal protection, thermal throat, scheduled
and distributed fuel injection. Types of nozzles and nozzle flow, Combined
cycle engines- turbo-ramjet, Air turbo-rocket (ATR), ejector ramjet, Liquid-air
collection engine (LACE) - need, principle, construction, operation,
performance, pulsejet, types and working principle
3 NUCLEAR ROCKET PROPULSION Nuclear propulsion history, Power, thrust, energy. Nuclear fission- basics, sustainable chain
reaction, neutron leakage, control, reflection, prompt and delayed neutrons, thermal
stability. Principles and fuel elements. The nuclear thermal rocket engine, start-up and
shutdown. Development status of nuclear engines, alternative reactor types, safety issues in
nuclear propelled missions. Solid core , liquid core, gas core, fission propulsion, LANTR, other
advanced nuclear rockets

4 Electrical propulsion Electrical propulsion systems, Definitions, thrust equations, performance parameters,
Limitations of chemical rocket engines. Electric propulsion systems- structure, types,
generation of thrust. Electrostatic thrusters, electromagnetic thrusters, applications to space
missions, pulsed plasma thrusters (PPT) for micro-spacecraft, solar electric propulsion.

5 Propellantless Propulsion Micro-propulsion, application of MEMS, chemical, electric micro- thrusters, principle,
systems description, Propellantless propulsion, teethers, momentum exchange, Photon rocket,
beamed energy propulsion, solar, magnetic sails

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1) Aircraft Propulsion and Gas Turbine Engines by Ahmed F.El-
Sayed
2) Cornelisse, J. W., Schoyer H.F.R. and Wakker, K.F., Rocket
propulsion and space flight Dynamics, Pitman, 1979.
3) Turner, M.J.L., Rocket and Spacecraft Propulsion, Springer, 2001.
4) Fundamentals of Jet Propulsion with Applications by Flack,
R.D.
5) Elements of Gas Turbine Propulsion by Mattingly J.D.
6) Roy Bhaskar,Aircraft Propulsion, 2008,Elseiver, India
7) William R Corliss, Propulsion systems for space flight, Mc
Graw Hill, 1970.
8) Philip Hill, Carl Peterson, Mechanism and Thermodynamics
of Propulsion, Pearson, 2010.
9) D P Mishra, Fundamentals of Rocket Propulsion, CRC Press,
2017.
10) William Emrich, Principles of Nuclear Rocket Propulsion,
Elseivier, 2016.

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LEARNING OUTCOMES

 The operating principle of ramjet, combustion and

its performance.
 Working of electric, ion and plasma thrusters
 The fundamental of nuclear rockets and its future
scope
 The basics of micro propulsion, solar sails and its
operating principle.
 Two Basic Classification

AIR BREATHING NONAIR BREATHING

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Propulsion systems can be subdivided into two broad
categories: air-breathing and non-air-breathing.

Airbreathing propulsion systems include the reciprocating,

turbojet, turbofan, ramjet, turboprop, and turboshaft engines.
Non-airbreathing engines include rocket motors, nuclear
propulsion systems, and electric propulsion systems.

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1 Rankings based on SpaceWorks’ Launcher Maturity Index, a subjective assessment of launch vehicle operators based on a variety of factors – please see end notes 2 SSO payload estimated and normalized from available data when necessary 3 Estimated
 FEEP—Field effect electric propulsion systems have been extensively studied in Europe,
where TRL is the highest.

Superconductivity—It is an area common to many present and future propulsion systems. It can
substantially improve electric propulsion, railguns, and future nuclear propulsion. It will enable spin-offs for
commercial and consumer applications too

Laser propulsion—This is an interesting concept applicable to microsatellites and frequent

access to space.

Solar sail—It is very interesting not only in terms of thin sail technology involved, but also because it will
perform a new class of missions.

MAGLEV—This concept could improve access to space by its impact on both cost and frequency of
mission scenarios.

Rubbia’s engine—An Italian project with very high-performance promise it is not yet developed anywhere
and could benefit from other available EU know-how

VASIMR—Intrinsically capable of trading Isp for thrust at constant power (a “dual-mode” concept), it can benefi t
many interplanetary missions.

ISPU—As regards to a manned Mars mission, it is a question of when rather than “why.” ISPU is capable of two
kinds of critical tasks: saving mass and using in situ resources.
Nuclear Powered Electric Rocket

Electric rockets (such as the ion engine) also have high Isp values. However,
they also have low thrust —typically because to throw large quantities of
reaction mass out of an electric rocket, you need immense amounts of
electric power. As of today, we have just one compact, long-lasting source of
such amounts of power, megawatts and above: the nuclear fission reactor.
So the idea is to couple a fission reactor to an ion engine
 PROPULSION

Non Air-Breathing
Air-Breathing Propulsion
Propulsion
Aircraft Proplsion-1 Aircraft Propulsion – II
• Advanced Air breathing Engines

Ramjet Scramjet
• Rocket Propulsion Systems

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 Basic Jet Engines Types
Aircraft Jet Engines

Turbojet Turboprop Turbo shaft Turbofan Un ducted Ducted Fan

Prop fan Engine

After Propeller / Rotor drivenby

Burning free turbine

Propeller / Rotor on
Non compressor Shaft
After Single Propeller fan
Next Slide
Burning

Counter rotating propeller

fan
Why we have to study AP-1 & AP-II..!? Contd..
PROPULSION

Non Air-Breathing
Air-Breathing Propulsion
Propulsion

Aircraft Proplsion-1 Aircraft Propulsion – II

• Introduction to AircraftJet • Ramjet &Scramjet Engine
Propulsion • Introduction to Rocket
• Piston – Propeller Engines for Propulsion
Aircraft
• Fundamentals of Rotating
• Liquid Propulsion systems
Components • Solid Propulsion Systems
• Compressors andTurbines • Hybrid Propulsion Systems
• Combustion Systems (Combustion Instability)
• Advanced air – Breathing • Advanced Propulsion Systems
Propulsion
• Ramjet &Scramjet Engine
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GAS GENERATOR

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By adding an inlet and a nozzle to the gas generator, a turbojet
engine can be constructed.

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TURBOJET ENGINE

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TURBOPROP ENGINE

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TURBOFAN ENGINE

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TURBOSHAFT ENGINE

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In the compressor, pressure and temperature increase as a result of
work.
The temperature of the gas is further increased by burning fuel in
the combustor.
In the turbine section, energy is being removed from the gas stream
and converted to shaft power.
he energy is removed by an expansion process that results in a
decrease of temperature and pressure.
In the nozzle, the gas stream is further expanded to produce a high
exit kinetic energy.
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After Burner

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The ramjet 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.
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In the past few years, research and development have been done on
a ramjet that has the combustion process taking place at supersonic
velocities.
By using a supersonic combustion process, the temperature rise and
pressure loss due to deceleration in the inlet can be reduced. This
ramjet with supersonic combustion is known as the scramjet
(supersonic combustion ramjet).

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