Module 1 Flashcards
He patented a jet propulsion in 1913 but was an athodyd that was very similar to modern day aircraft, but during that period, it was impossible to manufacture or use since heat resisting materials have nit been developed yet.
Rene Lorin
Athodyd means?
Aero
Thermo
Dynamic
Duct
Aero for ?
Thermo for ?
Dynamic for ?
Duct for ?
Aero for Air
Thermo for Temperature
Dynamic for Change
Duct for Shape
He had his first patent granted for using gas turbine to produce a propulsive jet in 1930.
Frank Whittle
It took him 11 years for the engine to complete its first flight.
Frank Whittle
His engine formed the basis of the modern gas turbine engine that lead to the development of twin-spool, triple spool, by-pass, ducted fan, unducted fan and propfan.
Frank Whittle
applies the same basic principles with piston engine propeller combination
WHITTLE-TYPE TURBOJET ENGINE
is an application of Sir Isaac Newton’s 3™ law of motion.
JET PROPULSION
is a piece of an apparatus designed to accelerate a stream of air or gas and to expel it to a high velocity.
JET PROPULSION ENGINE
is an internal phenomenon that results from the pressure of the jet on the atmosphere.
JET REACTION
Types of Jet Engine
- Ram Jet
- Pulse Jet Engine
- Rocket Engine
- Gas Turbine Engine
- Turbo/ Ram Jet
- Turbo Rocket
- No major rotating parts and consists of a duct with divergent entry and a convergent or convergent divergent exit.
Ram Engine
- Often the powerplant for missiles and target vehicles.
Ram Jet
- Unsuitable as an aircraft powerplant because it requires a forward motion imparting to it before any thrust produced.
Ram Jet
OPERATION: a. Forward motion is imparted to the engine from external source.
b. Air is forced into the air intake losing its velocity or kinetic energy increasing its pressure energy while passing through the diverging duct.
c. The total energy is increased by combustion of fuel causing acceleration of these gases through the outlet duct.
Operation of Ram Jet
- Uses the principle of interment combustion.
- Can be run at a static condition
PULSE JET ENGINE
Engine is formed by aerodynamic duct similar to the ram jet but involves higher pressure therefore needs more robust construction.
PULSE JET ENGINE
have been designed for rotor propulsion.
PULSE JET ENGINE
Unsuitable as an aircraft powerplant because it has high fuel consumption and is unable to equal the performance of modern gas turbine engine.
PULSE JET ENGINE
OPERATION:
a. Air drawn through the open valves passes into the combustioy, chamber and is heated by the burning fuel injected.
b. Because of this, an expansion occurs causing a rise in pressure forcing the valves to close and these expanding gases are ejected rearwards.
c. A depression is created by the exhausting gases allow the valves to open and repeat the cycle.
OPERATION OF PULSE JET ENGINE
- Does not use atmospheric air as the propulsive airstream.
ROCKET ENGINE
- Produces its own propelling fluid by the combustion of liquid or chemically decomposed fuel with oxygen, which it carries thus enabling it to operate outside earth’s atmosphere.
ROCKET ENGINE
- Suitable for operation over short periods.
ROCKET ENGINE
Uses a turbinedriven compressor as a means of producing thrust at low speeds.
GAS TURBINE ENGINE
draws air from the atmosphere. It compresses and heats the air. The energy and momentum of the air forces it out of the propelling nozzle at a velocity of up to 2,000 ft/sec. The air powers up the turbine to drive the compressor.
TURBO-JET ENGINE
Main Parts of Gas Turbine Engine
compressor
turbine
combustion chamber
Combination of turbo-jet (MACH 3) and ram jet engine
TURBO/ RAM JET
Good performance at high MACH numbers.
TURBO/ RAM JET
Suitable for aircraft requiring high speed and sustained high MACH number cruise conditions in which the engine operates in ram jet mode.
TURBO/ RAM JET
OPERATION:
a. During takeoff and acceleration, the engine functions as a conventional turbo-jet with the afterburner lit.
b. During cruise, the afterburner is inoperative.
c. As the aircraft accelerates through Mach 3, the turbo-jet is shut down.
d. The intake air is diverted from the compressor, by guide vanes, and ducted straight into the after burning jet pipe which becomes a ram jet combustion chamber.
Operation of Turbo/ Ram Jet
Considered as an alternative engine to the turbo/ram jet engine.
TURBO-ROCKET
It carries its own oxygen to provide for combustion.
TURBO-ROCKET
It is smaller and lighter but with higher fuel consumption.
TURBO-ROCKET
Suitable for an interceptor or space launcher-type aircraft.
TURBO-ROCKET
Has a flight plan that is entirely accelerative and of short duration.
TURBO-ROCKET
The development of the gas turbine engine as an aircraft power
plant has been so rapid that it is difficult to appreciate that
prior to the (?) very few people had heard of this method of
aircraft propulsion.
1950s
is a practical
application of Sir Isaac
Newton’s third law of motion
which states that, ‘for every
force acting on a body there is
an opposite and equal reaction.
Jet propulsion
is an internal phenomenon
and does not, as is
frequently assumed, result
from the pressure of the
jet on the atmosphere.
JET REACTION
is a piece of
apparatus designed to
accelerate a stream of air
or gas and to expel it at
high velocity.
JET PROPULSION ENGINE (Jet propulsion engine,
whether rocket, athodyd, or turbo-jet, )
Briefly, this means that the product of the
pressure and the volume of the air at the various stages in
the working cycle is proportional to the absolute
(?) of the air at those stages.
temperature
There are three main conditions in the engine working
cycle during which these changes occur.
compression
combustion
expansion
1.During (?), when work is done to increase the
pressure and decrease the volume of the air, there is a
corresponding rise in the temperature.
compression
During (?), when fuel is added to the air and
burnt to increase the temperature, there is a
corresponding increase in volume whilst the pressure
remains almost constant.
combustion
During(?), when work is taken from the gas
stream by the turbine assembly, there is a decrease in
temperature and pressure with a corresponding increase
in volume.
expansion
When the air is compressed or expanded at 100 per cent
efficiency, the process is said to be (?).
ADIABATIC
during compression, a rise in the (?) of the air is
required and not an increase in its velocity.
pressure
After the air has been heated and its internal energy
increased by combustion, an increase in the (?) of
the gases is necessary to force the turbine to rotate.
velocity
At the (?) a high exit velocity is required,
for it is the change in the momentum of the air that
provides the thrust on the aircraft.
propelling nozzle
Book used by Bernoulli
Hydrodynamica
addition book of hydrodynamica (for air)
Pneumatics
is a variant of
ajet enginethat has been optimized to drive apropeller.
Turboprop
is a variant of ajet enginethat has been optimized to produce shaft power to drive machinery instead of producingthrust.
Turboshaft
(?) sometimes referred to as a fanjet or bypass engine, is ajet enginevariant which producesthrust using a combination of jet core efflux and bypass air which has been accelerated by a ducted fan that is driven by the jet core.
Turbofan
