Gas turbines are widely used for producing electricity, operating airplanes and for various industrial applications such as in refineries and petrochemical plants. The basic gas turbine cycle has low thermal efficiency so it is important to look for improved gas turbine based cycles.
It is well known that ambient temperature, humidity and pressure are important factors in gas turbine performance. Thermodynamic analyses exposed that thermal efficiency and specific output decrease with an increase of humidity and ambient temperature as shown by Tsujikawa and Sawada [1]. Bird and Grabe [2] have studied the effects of humidity on gas turbine performance and formulated correlations for expressing relations between humidity and gas turbine performance. El-Hadik [3] carried out a parametric study on the effects of ambient temperature, pressure, humidity and turbine inlet temperature on power and thermal efficiency. He concluded that the ambient temperature has the greatest effect on gas turbine performance, which increases with the turbine inlet temperature and pressure ratio. Reductions of power and efficiency due to a 1 K temperature growth were found to be around 0.6 and 0.18% respectively.