Energy and exergy analysis of reverse Brayton refrigerator for Gas Turbine power boosting

In this study the use of Reverse Brayton cycle to boost up the power of gas turbine power plants operating in hot humid ambiance is analysed by the energy and exergy methods. The gas turbine inlet temperature is reduced by mixing the chilled air from Brayton refrigeration cycle and the main intake air stream reaching low intake temperatures. In this paper the effect of irreversibilities in the system components have been evaluated along with the exergetic power gain ratio, and the exergetic thermal efficiency change, of the cycle. The energy analysis results indicated that the intake temperature could be lowered below the ISO standard with maximum power increase up to 19.58% and appreciable decrease in the thermal efficiency (5.76% of the site value). Whereas, the exergy analysis approach showed that the power gain could only be 14.66% as a result of the components irreversibilities.