Thermodynamic modeling and second law based performance analysis of a gas turbine power plant (exergy and exergoeconomic analysis)

It this research paper, a complete thermodynamic modeling of one of the gas turbine power plants in Iran is performed based on thermodynamic relations. Moreover, a complete computer code is developed for the simulation purposes using the Matlab software. To assess the system performance, exergy and exergo-economic analysis are conducted to determine the exergy destruction of each component and cost of each flow line of the system. A complete parametric study is also carried out to study the effect of some design parameters such as exergy efficiency and total cost of exergy destruction on the system performance variation. The exergy analysis results have revealed that combustion chamber (CC) is the most exergy destructor component compared to other cycle components. Also, its exergy efficiency is less than other components which is due to the high temperature difference between working fluid and burner temperature. In addition, it was found that by an increase in the TIT (gas turbine inlet temperature), the exergy destruction of this component can be reduced. On the other hand, the cost of exergy destruction, which is a direct function of exergy destruction, is high for combustion chamber. The effects of design parameters on exergy efficiency have shown that an increase in the air compressor pressure ratio and TIT increases the total exergy efficiency of the cycle. Furthermore, the results have revealed that by an increase in the TIT for about 350 K the cost of exergy destruction can be decreased for about 22%. Therefore, TIT is the best option to improve the cycle losses.