Topic 01 v2 - History of Gas Turbine Engines and Introduction to Jet Propulsion Flashcards
states that for every force acting on a body, there is an opposite and equal reaction
Isaac Newton’s Third Law of Motion
the force which is generated in the opposite direction to that of a discharge of fluid under pressure, escaping through an opening.
jet propulsion
consisted of a sphere into which steam was introduced under pressure
hero’s engine
The steam escaping through nozzle mounted opposite one another on the surface of the sphere, created thrust, which caused the sphere to rotate around its axis.
hero’s engine
One of the first attempts in developing jet powered aircraft resulted in the development of a hybrid design. Compressor output was mixed with fuel, the combination was burnt and jet thrust resulted.
Campini Camproni CC-2
Year earlier than CC-2, the Germans had flown their version of a jet powered aircraft, ___________.
Heinkel 178
Heinkel 178 was powered by an engine designed by young German scientist _____________.
Hans von Ohain
submitted patents for his jet engine in 1930 but it was not until 1939 that sufficient financial and technical backing was found to enable him to manufacture a flyable version of his engine
Sir Frank Whittle
When did Sir Frank Whittle submit patents for his jet engine?
1930
When did Sir Frank Whittle secure financial backing to manufacture his jet engine?
1939
The __________ had initially been contracted to
produce the Whittle engine, but ____________ eventually
took over the development of the engine.
firm of Rover, Rolls Royce
Aircraft that utilized the Whittle engine
Gloster E28/39
Rolls Royce reworked the Whittle engine to produce the ‘__________’ engine.
Derwent
Later versions of the Derwent engine, capable of __________ of thrust, were used to power the _______________.
3,600 lb, Gloster Meteor F8
During a visit to the United States, the leader of the Rolls Royce design team found that the Americans were developing engines capable of producing up to ____________.
4,000 lb of thrust,
A project which at the time was the most powerful engine in the world, with 5,000 lb of thrust.
Nene engine
Propulsion Devices
- Air Breathing
- Rocket
Propulsion device that uses atmospheric air and some fuel as main propellant.
Air Breathing
Examples of air breathing propulsion device
- piston engines
- ramjet
- scramjet
- pulsejet
- gas turbine engines
Propulsion device that carries the entire propellant composed of liquid or solid fuel and the oxygen.
Rockets
Basic operation of jet propulsion engines
- Air enters through the air intake.
- Air is compressed by passage through the compressor.
- Air is mixed with fuel in the combustion chamber.
- Fuel is ignited; Pressure and Temperature raised.
- Some of the pressure is used to turn the turbine.
- Turbine shaft drives the compressor.
- Hot and high-pressure air is forced through the nozzle.
- The reaction force is the engine thrust.
The main function of any airplane propulsion system is?
to provide a force to overcome the aircraft drag, called thrust
Newton’s 2nd Law of Motion
force equals mass
accelerated (F = ma)
When a jet engine accelerates ___________, it makes thrust (force).
air (mass)
Two ways to increase jet engine
- Increase the speed of exhaust gases
- Increase the quantity of exhaust gases
Increased _____________ will make an aircraft fly faster or with more weight.
engine thrust
Types of Jet Engines
- Gas Turbine Engine
- Ramjet
- Pulsejet
- Scram Jet
- Rocket Engine
by far the most practical form of jet engine in use today
gas turbine engine
the standard on nearly all transport category, business, and military aircraft
gas turbine engine
Works in the same manner as a reciprocating engine but all events happen simultaneously.
gas turbine engine
An athodyd (aero-thermodynamic-duct) which has no rotating parts and consists of a duct with a divergent entry and a convergent or convergent-divergent exit.
ramjet
With a forward motion imparted by an external source, air is forced in the divergent inlet (increasing its pressure) the total energy of air is further increased by combustion of fuel and the rapid expanding gases accelerate to the atmosphere through the outlet duct.
ramjet
Can be run at static conditions unlike the ram jet and is constructed with a robust construction.
pulse jet
Pulse Jet: Inlet duct has ___________________ to the open position.
spring loaded inlet valves
Pulse Jet: As air passes to the combustion chamber, it produces _____________ as to force the valves close. As the exhaust gases exits, this creates a _____________ that allows the valves to open and repeat the cycle.
high pressures, low pressure
Unstable as a powerplant due to high fuel
consumption and cannot match performance of
modern gas turbine engines.
pulse jet
Other name of scramjet
supersonic combustion ramjet
a variant of a ramjet air breathing jet engine in which combustion takes place in supersonic airflow
scramjet
A scramjet relies on ______________ to compress the incoming air forcefully before combustion but the airflow is ______________
throughout the entire engine.
high vehicle speed, supersonic
A jet engine that does not use atmospheric air as a propulsive fluid stream (non-air breathing).
rocket engine
Uses propellants thus enabling outside atmosphere operations.
rocket engine
GTE Principles: Mass x Acceleration = Force where acceleration is the difference between the ____________
of the air to that of its ______________ due to the addition of the _____________.
outlet velocity, inlet velocity, heat energy
In gas turbine engines, combustion occurs at constant ____________.
pressure
GTE Principles: Mass x Acceleration = Force where the mass is the _______________.
air delivered by the compressor
Power is developed in the ________ of the engine.
turbine
The processes occur in a __________ manner in a gas turbine engine.
continuous
In the piston engine, only one stroke is utilized in producing power, the other three are effectively absorbing power. In the gas turbine engine, the _______________ have been eliminated, thus allowing more time for the burning of fuel.
three ‘idle’ strokes
Theoretically, combustion in the gas turbine occurs at a constant ___________. This is achieved partly because of the continuous process of the __________ cycle, and also the fact that the __________________ is not an enclosed space.
pressure, Brayton, combustion chamber
