Question

A jet engine is operating at an altitude of 7000 m. The mass of air passing through the engine is 46 kg/s and the heat addition in the combustion chamber is 500 kJ/kg. The cross-sectional area of the combustion chamber is 0.5 m2, and the air enters the chamber at a pressure of 80 kPa and a temperature of 80°C. After the combustion chamber, the products of combustion, which can be assumed to have the properties of air, are expanded through a convergent nozzle to match the atmospheric pressure at the nozzle exit. Estimate the nozzle exit diameter and the nozzle exit velocity assuming the flow in the nozzle is isentropic. State the assumptions that have been made.

Answer 1