A Numerical and Thermodynamic Study on Application of a Recuperator on Thermal Efficiency and Emission of Pollutants in a Gas Power Plant

Over the past few years, researchers were carried out a conscious effort to explore various methods of improving the thermal efficiency of power plants. It was shown that the application of a recuperator is beneficial to improve the thermal efficiency of a gas power plant. Nevertheless, a few studies were done from a thermodynamic point of view and it is safe to say that few numerical simulation studies were performed using computational fluid dynamics. Therefore, in this study, the effect of using a recuperator was investigated to increase the temperature of the combustion chamber inlet air at four different temperatures (633, 643, 663 and 673 K) and to enhance the overall thermal efficiency. Furthermore, the effect of this approach on the emission of pollutants was explored. For this purpose, the compressor and turbine were numerically simulated using a developed MATLAB code while the combustion chamber of the gas power plant was simulated for various pre-heated temperatures in a thermodynamic analysis by ANSYS Fluent 16. The results indicated that in the case of the highest increase in the inlet air temperature to the combustion chamber (50°C) compared to the basic state (without recuperation), the thermal efficiency of the power plant and emission of nitrogen oxides were increased by 1.46% and by 44.17%, respectively.