Performance Evaluation of Simple Aero Gas Turbine Cycle with Transpiration Cooling of Gas Turbine Blades

Aero gas turbine engines have been using mainly film cooling and convection cooling techniques. For operating at high gas temperature amongst different cooling options the transpiration cooling technique has emerged as the most promising technique to improve the gas turbine cycle performance by allowing higher turbine inlet temperatures. This paper investigates the advantages of transpiration cooling technique over film cooling used in simple aero gas turbine cycle. The effects of variation of TIT and compressor pressure ratio on cycle performance are presented. TSFC with transpiration cooling is slightly higher than with film cooling in higher TIT range. However comparatively greater specific thrust is obtained with transpiration cooling than with film cooling. At a TIT of 1900 K and compressor pressure ratio of 21 the specific thrust developed with film cooling is 980 N-s/kg while that with transpiration cooling is 1013 N-s/kg.