Flow and Heat Transfer Characteristics of Large-scale Grooved Deep Blade Tip under Variable Working Conditions
In order to study the flow and heat transfer characteristics of the tip clearance with tapered sur-face grooves at different depths,for a high pressure turbine,by changing the groove depth under five typ-ical working conditions of the engine,the k-ω turbulence model and the adaptive turbulence simulation method(SATES)are used to carry out steady and unsteady numerical simulation analysis respectively.The results show that the groove depth is an important factor affecting the tip leakage flow and heat trans-fer characteristics,and the influence trend is also limited by the working conditions of the turbine.Com-pared with the deep groove,the clearance leakage of the shallow groove scheme is significantly reduced,and the corresponding total pressure loss coefficient of the turbine blade outlet is also reduced,which is particularly obvious in the low flow mass working conditions.However,the deep groove design performs better in reducing the thermal load of the blade tip.The average Nusselt number of the blade tip of the groove depth 0.8H scheme is 38.3%-95.3%lower than that of the groove depth 0.1H scheme.The steady and unsteady calculation methods mainly affect the predicted values of the local leakage in the gap and the heat load in the front of the blade tip,and do not change the distribution trend of flow and heat transfer characteristics.
turbine blade tipshrinkage surface grooveslarge scale groovegap flowblade tip heat transfer
万方数据
维普
