Engine Pressure Variation - EPR An animated version of this slide is also available. Most modern passenger and military aircraft are powered by gas turbine engines, which are also called jet engines. The first and most simple type of gas turbine is the turbojet . On this slide we show how the flow pressure varies through a typical turbojet engine. The pressure is color-coded with blue indicating the lowest pressure and white the highest pressure.
Air is brought into the turbojet through the inlet at the left of the computer drawing.
At the rear of the inlet, the air enters the compressor. The compressor acts like many rows of airfoils, with each row producing a small increase in pressure. At the exit of the compressor, the air is at a much higher pressure than free stream. In the burner a small amount of fuel is combined with the air and ignited at near constant pressure. Leaving the burner, the hot exhaust is passed through the turbine.