Question

A turbojet engine is fitted to an aircraft flying at M = 0.85 in conditions where the

ambient temperature is 216 K and the ambient pressure is 18.75 kPa. You are to

assume adiabatic flow and isentropic conditions.

The following data on the engine are known:

Compressor pressure ratio ?? = 12

Combustion chamber efficiency ?? = 1

Turbine Inlet temperature ?4 = 1796 ?

Calculate:

a) The total temperature and pressure at entry to the compressor. (6 Marks)

b) The total temperature and pressure at entry to the combustion chamber.

c) Derive an expression for fuel-to-air ratio and then calculate the fuel-to-air ratio in the

combustion chamber.

Answer 1