The influences of turbine blade mean temperature and component efficiencies on coolant optimization in the gas turbine

Abstract

This paper continues the computational invcstigalion of optimum performance of a gas turbine configuration incorporating a gas generator, previously reported by the authors. Even for contemporary pressure ratios not previously considered, there appears to be no advantage in prebleeding the coolant air, and within the range considered, as previously found, the amount of coolant preheating has only a secondary effect on maximum engine efficiency. This is also true of the influence of allowable mean blade temperature on maximum engine efficiency, but both factors do have a pronounced effect on the optimum coolant and where maximum cycle efficiency is primarily determined by compressor pressure ratio and component isen-tropic efficiencies. The specific work output is confirmed under optimum conditions to be an almost linear function of the compressor turbine inlet temperature.