Simulation Of Cooling Effectiveness Of HP Turbine Blade And Optimal Design Of Film Cooling

Because of higher combustor exit temperature, blade coolingtechniques has become the key technology of turbine blade design. Usingmore effective blade cooling techniques is essential to increase reliabilityand life of turbine blade, reduce the cost of high-temperature resistantmaterial and cut the consumption of cooling air. In this paper, flowcharacteristics, distribution of temperature and the factors affecting theaverage temperature and cooling effectiveness of a high-pressure turbineblade were studied by conjugate heat transfer methodology. Optimaldesign of film cooling was also presented on the high temperature zone ofblade.In this paper, the accuracy of different turbulence models wasverified by conjugate heat transfer calculation to provide the basis ofnumerical analysis for subsequent calculation. The flow characteristicsand the temperature distribution of the turbine blade were obtained, andthe reasons for the higher temperature at blade back were analyzed. Theeffects of flow rate, temperature rate and mainstream Reynolds on the average temperature and cooling effectiveness were calculated. Theresults showed that the flow rate had greater impact on averagetemperature and cooling effectiveness than temperature rate andmainstream Reynolds, while the temperature rate and mainstreamReynolds had little impact on the cooling effectiveness. Dustpan-shapedand fan-shaped holes were considered when doing the optimal design.Comparison between novel holes and round holes in single row underdifferent blowing ratio was carried out. The results showed that the filmcooling efficiency of dustpan-shaped and fan-shaped holes was obviouslyhigher than that of the round holes. The conditions of film separation withdifferent hole shapes were summarized, and the reasons of better coolingeffect of novel holes were explained by the phenomenon of cooling jetvelocity vector. Finally, the novel holes were applied to the suction sideof high-pressure turbine blade. Comparing with the original model, theoptimization results were satisfactory.