1. Show that the product of the compressor and turbine isentropic efficiencies must be greater than (TL/TH) 1/2 if a Brayton cycle gas turbine unit is to operate at its maximum power output.
2. A test on an open loop Brayton cycle gas turbine produced the following results:
- Net power output = 180:5 hp
- Air mass flow rate = 20:0 × 103 lbm/h
- Inlet air temperature = 80:0°F
- Inlet air pressure = 14:5 psia
- Compressor exit pressure = 195 psia
- Compressor isentropic efficiency = 85:0%
- Combustion chamber heat addition = 4:00 × 106 Btu/h
- Using a cold ASC analysis and assuming k = 1.40, determine
a. The cycle thermal efficiency.
b. The isentropic efficiency of the turbine.