At the start of cruise the temperature and pressure of the air entering the engine may be taken to be 259 .5K and 46.0 kPa. Assume a pressure ratio of 1.6 for flow through the fan which enters the core and a pressure ratio of 25 in the core compressor itself. Assume isentropic efficiencies of 90% in each component. Find the temperature rise across the fan of the flow entering the core compressor, the temperature entering the core compressor and thence the temperature at exit from the core compressor. The power produced by the core turbine must equal the power into the core compressor; since we are assuming a perfect gas with the properties of air and treating the combustion as equivalent to a heat transfer, the temperature drop in the core turbine must equal the temperature rise in the core compressor. If the temperature of the gas leaving the combustor (i.e. entering the HP turbine) is 1450K, find the temperature at core turbine outlet and thence the pressure at outlet from the core turbine. Assume a turbine efficiency of 90%. (Neglect any pressure drop in the combustor.
At the start of cruise the temperature and pressure of the air entering the engine may be taken to
be 259 .5K and 46.0 kPa. Assume a pressure ratio of 1.6 for flow through the fan which enters the core
and a pressure ratio of 25 in the core compressor itself. Assume isentropic efficiencies of 90% in each
component. Find the temperature rise across the fan of the flow entering the core compressor, the
temperature entering the core compressor and thence the temperature at exit from the core compressor.
The power produced by the core turbine must equal the power into the core compressor;
since we are assuming a perfect gas with the properties of air and treating the combustion as equivalent
to a heat transfer, the temperature drop in the core turbine must equal the temperature rise in the core
compressor. If the temperature of the gas leaving the combustor (i.e. entering the HP turbine) is
1450K, find the temperature at core turbine outlet and thence the pressure at outlet from the core
turbine. Assume a turbine efficiency of 90%. (Neglect any pressure drop in the combustor.)
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