الفهرس 
Chapter One: IntroductionOnly 14 pages are availabe for public view
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Abstract
Combined cycle power plants (CCPPs) are a fossil fuel fired plants which utilize the exhaust gases coming out of the gas turbines (GTs) to produce steam which is fed to the steam turbine (ST) to produce electric power with a higher thermal efficiency than using either gas turbine (GT) or steam turbine (ST) plants individually. The recently installed combined cycle power plants (CCPPs) can outstand 60 percent efficiency at their site design conditions such as Beni-Suef combined cycle power plant (CCPP), which is our study case. Beni-Suef combined cycle power plant (CCPP) is one of Egypt’s highest capacity and most developed power plants, and even one of the world’s highest. It is designed to have four identical modules. The basic configuration for each module is two gas turbines (GTs), two heat recovery steam generators (HRSG), a steam turbine (ST) and three generators. The plant has a nominal grid capacity of approximately 4800 MW (1200 MW / module). [1]
Many factors influence the efficiency of any combined cycle power plant (CCPP) with respect to the environmental conditions of the place where it is installed, for instance ambient temperature, ambient air pressure, relative humidity (RH) and cooling water inlet temperature. It is aimed in this work to determine the impact of changes of dead state conditions like ambient temperature and air relative humidity (RH) on the performance of major components of Beni-Suef combined cycle power plant (CCPP) and on the overall performance of the plant, based on the comprehension of energy and exergy principles. For this purpose, the in-operation data of one module have been recorded to be used in the study. Analysis of energy and exergy for the selected Beni-Suef combined cycle power plant (CCPP) module was performed at 16.1, 28.1, 37.6 oC ambient temperatures.
It was concluded that an increase of 1 oC in ambient temperature causes a decrease of 7.0446 MW, 0.111% and 0.0835 % in the selected module of Beni-Suef combined cycle power plant (CCPP) gross power output, efficiency and second law efficiency respectively.
Also, it was concluded, that the largest exergy destruction rate was found in gas turbines (GTs) combustion chambers (CCs) ( around 86% of the total exergy destruction rate) in all tested ambient temperature conditions. Their percentages comparing with the whole combined cycle power plant (CCPP) exergy destruction increase with the rise of ambient air temperature while their exergy destruction levels decrease as air and fuel mass flow rates decrease with rising ambient temperatures.
The effect of relative humidity (RH) on one gas turbine (GT) unit was also studied at 16.1, 28.1, 37.6 oC ambient temperatures and changed relative humidity ratios (RH) from 10 to 90 %. It was found that, the exergy destruction of gas turbine (GT) compressor increases with the increase in air relative humidity (RH) this leads to increase compressor work and a further reduction in gas turbine (GT) net power. It was concluded as well that, the sensitivity of the gas turbine performance towards the change of air relative humidity (RH) increases with the increase of ambient temperature.