Thermodynamic analysis of an enhanced gas and steam cycle

The most efficient engine is not an internal nor external combustion engine, but the two combined. What is now the traditional combined gas and steam turbine uses the gas turbine for the topping cycle and heat is recovered from the exhaust to heat, boil and superheat water for a Rankine cycle. A newer concept will be to use steam for the Rankine cycle for cooling of the turbine blades and the hot gas path of the gas turbine. This can enhance efficiency by allowing a higher temperature to the gas turbine while providing additional heat recovery for the bottom steam cycle. This paper will develop and demonstrate a methodology to compare the enhanced combined cycle with a traditional combined cycle.