Practically all airborne jet engines use an axial-flow compressor, in which the
air flows generally in the direction of the shaft axis through alternate rows of stationary and rotating blade, called statiores and rotors. The blades are arranged so that the air enters each row at a high velocity. As it flows through the blade passage the air is decelerated to lower velocity, thereby increasing the pressure 24 times in 15 stages, each of stators and rotors making up a stage.
The compressed air then enters the combustion chamber where it is mixed with fuel vapor and then burned. For best performance, the combustion temperature should be the maximum obtainable fome the complete combustion of the oxygen and the fuel. This temperature however, would make the turbine too hot; turbine inlet temperatures, with currently limit turbojet performance, cannot exceed about 1100 C because of the thermal limitations of the turbine inlet, only part of the compressed air is burned. Part of the air is mixed with the fuel and ignited; the remainder is used to cool the the turbine.
in then turbine, which acts in opposite fashion to the compressor, the gases are partially expanded through alternate stator passengers. At the entry to each blade row, the velocity is low, allowing the gas to expire and speed up in the passage while it turns the rotor. The turbine provides the power to dive the compressor.
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