Four processes occur in gas turbine engines. These processes were first discribed by George Brayton and called the Brayton Cycle, which occur in all internal combustion engines. The Brayton steps are as follows:
1.Compression occurs between the intake and the outlet of the compressor. During this process, pressure and temperature of the air increases.
2.Combustion occurs in the combustion chamber where fuel and air are mixed to explosive proportion and ignited. The addition of heat causes a sharp increase in volume.
3.Expansion occurs as hot gas accelerates from the combustion chamber. The gases at constant pressure and increased volume enter the turbine and expand through it.
4.Exhaust occurs at the engine exhaust stack with a large drop in volume and at a constant pressure.