Mini two-shaft gas turbine exergy analysis with a proposal to decrease exergy destruction

In this case study, exergy analysis is applied to a mini two-shaft gas turbine which is located in Islamic Azad University Khomeini Shahr Branch s Thermodynamics laboratory and a proposal presented to make exergy destruction less using a Heat Recovery Water Heater (HRWH). Calculations were done for N2=20000 (rpm) constant and various N1 and after that for N1=60000 (rpm) constant and various N2. Results revealed that the highest exergy destruction rate occurs in combustion chamber in all conditions and a huge part of exergy destruction through the turbine exhaust. Increase in N1 leads to increases in all component exergy destruction rates. On the other hand, power turbine is the only component which is affected by changes in N2 and the exergy destruction rate increases with increase in N2. Moreover, exergy gained rate within HRWH increased with increase in N1 and is almost constant with changes in N2. In the same vein, exergetic efficiency of HRWH and exergy gained rate within HRWH are increased with decrease in water outlet temperature of HRWH.

Keywords:

Gas Turbine , Exergy Analysis , Second Law Efficiency , Exergy Recovery