Department of Mechanical Engineering, University of Sistan and Baluchestan, Zahedan, Iran
It is important to study real thermodynamic systems and evaluate the inefficiency of thermodynamic components in power plants in order to improve their performance. In this work, exergy analysis and investigation of the gas turbine segment of the Kerman combined cycle, are examined. The results reveal that the most exergy efficiency defect is related to the combustion chamber and compressor and finally to the gas turbine, respectively, and also in the combustion chamber the irreversibilities are mainly due to chemical nonequilibrium, thermal nonequilibrium, and mechanical nonequilibrium caused by combustion; 22.835% of exergy is lost during the combustion process. Therefore, this work introduces and defines ecological - cost or ecologicost as a new criterion. Ecologicost indicates that dissipated energy is more than production power; In other words, the system is defective and needs to be repaired or replaced. Ecologicost has the potential to replace traditionally criteria. Moreover, the ecological function and ecologicost value of the gas turbine are -20.418 MW and -0.05701, respectively. This Negative number indicates that system goes to destruction and needs repair or replacement or improvement. The optimization results show that the maximum power, maximum energy efficiency, maximum exergy efficiency, maximum ecological, and maximum ecologicost are 136.437 MW, 38%, 48.39%, 6.069 MW, and 0.01695, respectively.