Abstract

In this paper, MATLAB simulation investigation for optimum Work net and optimum efficiency of combined cycle (Intercooled) power plant using different fuels with supplementary heat from HRSG are presented. The HRSG structures (steam pressure, maximum temperature and mass flow rate) are designed system composed by HRSG and steam turbine (ST). The analysis procedure is followed for finding both optimums Worknet and optimum efficiency. A fraction of hot gases heat from combustion chamber is bypassed to HRSG. Exit heat from gas turbine also passed through the HRSG. The simulation is carried out for different fuels (Nepthalene, CNG, LNG and Kerosene), air fuel ratios (50, 55 and 60) for different pressure ratios. The simulation codes are made in MATLAB. The evaluation shows that use of HRSG is particularly convenient in the perspective of efficiency increase it can be a valid technical solution aiming to up gradation of existing combined cycle power plants. The significance of this kind of investigation gives advantages of combine power plant that utilizes the waste energy for generation of steam to run the steam turbines. This leads to increase in power output in thermal efficiency. The performance of combined cycle depends upon the number of parameters like pressure ratios, types of fuel used, component efficiency, turbine exhaust temperature, degree of supplementary heating and condition of steam generation. It is noticed that fraction hot gases bypassed from combustion chamber to HRSG certainly give sufficient heat energy to generate steam at required pressure and temperature to obtain the optimum Worknet and optimum efficiency significantly.

Keywords

combined cycle power plants, supplementary heating, HRSG, intercooled