Heat Pipe Cooling of IHPTET Phase III Turboshaft Engine Components

Heat pipes can potentially eliminate the need for bleed air cooling of high temperature components in gas turbine engines. The proposed innovation is to incorporate heat pipe technology to cool High Pressure Turbine nozzles in turboshaft engines. The use of heat pipe cooled HPT nozzles will help to achieve Integrated High Performance Turbine Energy Technology (IHPTET) Phase III goals including a reduction in specific fuel consumption (SFC) and an increase in shaft horsepower (SHP) for the turboshaft engines. Studies by AlliedSignal Engines have shown that heat pipe cooling of nozzles in IHPTET Phase II turboshaft engines could reduce spc by 1.6%; increase SHP by 1.8%; and increase turbine efficiency by 1.8%. These results will likely increase when considering the IHPTET Phase III engine. However, the transition of the heat pipe technology from the phase Ir engine to the Phase III engine requires considerable development because of the increased nozzle operating temperature. This proposal describes an effort to begin addressing the development issues. The work effort involves defining requirements, conducting analyses to determine the performance advantages, designing a heat pipe cooled HPT nozzle, and fabricating a proof-of-concept heat pipe and testing it under simulated Phase III engine operating. Heat pipe cooling of IHPTET Phase III HPT nozzles of turboshaft engines will be directly applicable to commercial turboshaft engines. Upon successful completion 0¿ Phases I and II, AlliedSignal Engines is expected to participate in the commercialization of the technology by incorporating the heat pipe cooled HPT nozzles into a demonstrator engine.