Problem 6.14 - An Aircraft Gas Generator Turbine

Consider an aircraft adiabatic gas generator turbine operating under the conditions shown in the diagram:

Ignoring kinetic and potential energy changes and assuming that the gas behaves as air with a mass flow rate of 4.55 kg/s, determine

• a) the actual work output of the turbine [220 kJ/kg]

• b) the isentropic work output of the turbine [275 kJ/kg ]

• c) the turbine adiabatic efficiency (η _T ) [80%]

• d) the actual power output of the turbine [1000 kW]

Derive all equations used starting from the basic energy equation for a flow system, the equation of enthalpy for an ideal gas (Δh), the basic definition of turbine adiabatic efficiency (η _T ), and the temperature/pressure relation for the isentropic process of an ideal gas:

Use specific heat values for air at 800K (C _P = 1.099 [kJ/kg.K], k = 1.354)