Elements Of Aeronautics - Vel Tech Dr.RR & Dr.SR Technical

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U3AEA04
ELEMENTS OF AERONAUTICS
Mr. SYED ALAY HASHIM
Assistant Professor
Department of Aeronautical Engineering
VEL TECH Dr. RR & Dr. SR TECHNICAL UNIVERSITY
Chennai
INDIA
I to V
UNIT
POWER POINT PRESENTATION
AIRCRAFT COMPONENTS
TYPES OF WING
1.
2.
3.
4.
5.
6.
7.
Monoplane
Biplane
Tandem wing
Triplane
Quadruplane
Multiplane
Canard wing
SWEEP WING
Leading edge extensions of various
kinds
AIRCRAFT
HISTORICAL RECORDS
Introduction
AEROSPACE ENGINES
• Comprehend the basic components of gas turbine
engines and their basic operations
• Comprehend the thermodynamic
occurring in a gas turbine engines
processes
• Comprehend the support systems associated with
gas turbine engines
Gas Turbine Cycle
Single stage Ideal gas turbine cycle
GAS TURBINE CYCLE
Two stage turbine cycle
Gas Turbine Cycle
Two stage Compressor and Turbine cycle
Jet Propulsion Cycle
In practical or actual cycle Entropy is not constant
Jet Engine
Basic Components
Compressor
•
•
Supplies high pressure air for combustion process
centrifugal flow and Axial flow
•
•
•
Centrifugal Compressor
Adv: simple design, good for low compression ratios (5:1), strong
Disadvantage: Difficult to stage, less efficient, high frontal area
Compressor
Axial flow
• Good for high compression ratios (20:1)
• Most commonly used
Turbine
• Convert the kinetic energy into expansion work
• It is used to drive the compressor as well as
propeller shaft
Comparison of Gas Turbine and
Piston Engine
Classification of Engine
Engine
Air Breathing Engine
Non-Air Breathing Engine
(Presents of Fuel and absents of Air
(Using atm air to produced Power)
Jet Engines
Reciprocating Engines
instead of Air + Oxidizer. Hypersonic
vehicles, Operating Mach No : 15 to 20)
(Propulsive thrust is produced by jet)
Rocket Engine
(No moving parts)
Gas Turbine Engine
Non-Gas Turbine Engine
(Available moving parts like
Compressor and Turbine)
Turbojet
Turboprop
(No moving parts)
Ramjet
Scramjet
Turbofan
Turbo-shaft
Pulsejet
Turbojet




Chemical energy is converted into mechanical energy
100% Thrust produced by Nozzle
Operating Mach No: 1 to 2
Supersonic Aircraft (1 to 5)
Turbofan




20 to 40% of Thrust produced by Nozzle
60 to 80% of Thrust produced by Fan
Operating Mach No: 0.4 to 0.8
High Subsonic Aircraft (0.3 to 0.8)
Turboprop




20 to 25% of Thrust produced by Nozzle
75 to 80% of Thrust produced by Propeller
Operating Mach No: 0.4 to 0.65
Subsonic Aircraft (0.1 to 0.8)
Turbo Shaft



High pressure turbine is used to
rotate HP & LP Compressor
Low pressure turbine is used to
rotate output Shaft
No Thrust produced in the exit
turbine gas
Turbo Shaft




Kinetic energy is converted to Shaft power
100% Thrust produced by Shaft
Operating Mach No: 0.4 to 0.8
High speed Subsonic helicopter (0.3 to 0.8)
Pulse Jet




Made up of few moving parts
Valved engines use a mechanical valve to control the flow of expanding exhaust,
forcing the hot gas to go out the back of the engine through the tailpipe
Starting the engine usually requires forced air and an ignition method such as a
spark plug for the fuel-air mix.
It can operate statically
Rocket Engines





A rocket is a machine that develops thrust by the rapid expulsion of matter
A rocket is called a launch vehicle when it is used to launch a satellite or other
payload into space
Rocket engines are reaction engines
The highest exhaust velocities
It is used in missile
Passenger airplanes
Sl. No.
Description
Less
Moderate
High
1
Specific fuel consumption
Turbofan
Turboprop
Turbojet
2
Noise Level
Turbofan
Turboprop
Turbojet
3
Operating Mach No
Turboprop
Turbofan
Turbojet
4
Take off Thrust
Turbojet
Turbofan
Turboprop
5
Altitude
Turboprop
Turbofan
Turbojet
6
Load Carrying capacity
Turbojet
Turboprop
Turbofan
7
Specific Impulse
Turbojet
Turboprop
Turbofan
Thrust Equation
Total Thrust = Momentum Thrust + Pressure Thrust



mi=mj (mass flow rate)
Inlet pressure = Exit pressure
Thrust force is the forward motion of engine
Factors Affecting Thrust
 PRESSURE
 TEMPERATURE
 DENSITY
 HUMIDITY
 ALTITUDE
 FORWARD VELOCITY
Methods of Thrust Augmentation
 After burning




High thrust for short duration
It is used only in take-off (or) for high climbing rates
Additional fuel is burning in the tail pipe between the turbine and exhaust
nozzle
It is increased the jet velocity
 Oxidizer-Fuel Mixture



Increase the mass flow rate
Evaporative cooling which produces higher pressure and higher mass flow rate
Increase the compressor pressure ratio due to reduced compressor air flow
 Water and menthol or alcohol Mixture
After burner
Oxidizer-Fuel Mixture
 Evaporative cooling which produces higher pressure and higher
mass flow rate
Advantages of Gas turbine Engines
•
•
•
•
•
•
•
•
Weight reduction of 70%
Simplicity
Reduced manning requirements
Quicker response time
Faster Acceleration/deceleration
Modular replacement
Less vibrations
More economical
Disadvantages of Gas Turbine Engines
•
•
•
•
•
Many parts under high stress
High pitched noise
Needs large quantities of air
Large quantities of hot exhaust (target)
Cannot be repaired in place
TYPES OF FUSELAGE STRUCTURE
FUSELAGE DESIGN
WING STRUCTURE
Thank you
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