Propulsion Of Flying Vehicles

CAFE Foundation
The CAFE Foundation is a U.S. non-profit aviation development and flight test organization based in Windsor, California. CAFE is an acronym for "Comparative Aircraft Flight Efficiency". The organization promotes experimental aviation activities which promote the development of highly efficient aircraft
Un poco de Historia
* In 1791, he was awarded the first patent for a gasturbine John Barber of England.
* The first internal combustion engines used a small gas engine to power a large propeller to help accelerate the air to generate thrust.
* 1938-1941 Hans von Ohain y Frank Whittle, their designs contain a compressor and a turbine on the same axis, beginning the era of jet propulsion.
* Invention of the jet engine
Jet engine rankings
A jet engine isa propulsive system whose operating principle is based on the application of the Second and Third Law of Newton.
Newton's 2nd Law: The increase in momentum is equal to the impulse of the applied force and has the same direction as that. Can also be expressed by saying that the total force exerted on a body equals the product of its mass times its acceleration.
Newton's 3rd law: Every action of aforce, there is an equal acting in the same direction but in the opposite direction.
Jet engines are those that use a variety of gases, ejected at high velocity and pressure, exert a force in the opposite direction, we could call or forward momentum.
Estatorreactores (Ramjet)
Lack of compressors and turbines, is the simplest.
the air which is under great pressure (due to the high speedof course plane) enters through the inlet diffuser ramjet where there is a smaller area, whereby its pressure andtemperature increase considerably, the next step is the combustion of all the air, thisprocess runs in the combustion chamber, which houses a series of nozzles which are responsible for expanding the finely atomized fuel continuously when fuel and air is found in the combustion chamber, the nextstep is performed by a series of spark plugs ignite the mixture responsible for this step as called combustion engines in most shows a lot ofheat (700 degrees C despite its cooling), therefore it is necessary a special tile for wallsof the ramjet. Finally exits the final mixing at high speed on the exhaust nozzle, which canbe of two different ways as needed, these can be: convergent (subsonicspeed) or diverging (supersonic).
Pulsoreactores (pulse jet)
pulse jets have inside valves that allow fuel to run the flashing at high frequency pulses.Leads to higher power, but at least it also has more mechanical components that tend to risks of mechanical failure.
Turboreactores (turbo jet)
Engines with open cycle turbines.
Must be within a compressor or turbocharger and a gas turbine (whichmoves thecompressor)
Turbochargers are generally used in the military, but gradually integrate into commercial aircraft.
They have excellent performance but suffer from inadequate power at takeoff. (lack of power at low revs)
For the operation of gas turbine and the compressor corresponds to the Brayton Cycle
Adiabatic-Compression
-Combustion at constant pressure. (Combustion theoreticallyconstant pressure and, indeed, a pressure lower than the end of compression, due to friction losses).
-Adiabatic expansion. (Expansion of gas in the turbine or turbines, capturing their energy, which is applied to move the compressor). (Expansion of the gas in the outlet nozzle, increasing the gas velocity, appearing a large increase in the amount of movement thatoccurs in thrust).
Turbofán(turbofan) turbosoplante, turboventilador
In a single-spool (or single-shaft) turbojet, which is the most basic form and the earliest type of turbojet to be developed, air enters an intake before being compressed to a higher pressure by a rotating (fan-like) compressor. The compressed air passes on to a combustor, where it is mixed with a fuel (e.g. kerosene) and ignited. Unlike a reciprocating...