Fluid Field Calculation And Structure Analysis Of Miniature Turbine Guide Vane

Turbine blade which is working under abominable condition of high cyclic temperature,aerodynamic load and mechanical load, is the key component of aero turbine engine. Increase the turbine inlet temperature is the important method to improve the thrust-to-weight ratio and thermal efficiency of aero turbine engine, and the temperature of combustion far exceeds the permissible heated temperature of the material of turbine blade. In order to ensure the cooling structure efficiency and the operating life of blade, it is necessary to get the accurate analysis of fluid field and strength. With the rapid development of CFD technique, numerical simulation which can predict the aerodynamic load and temperature load of blade, has gradually became an important tool in the design process of turbine blade. With the help of conjugate heat transfer methods and thermal mechanical methods, for the turbine blade, fluid field characteristic and strength have been studied.Conjugate heat transfer fluid field analysis and strength analysis has been done, which are based on the model of NASA-Mark? guide blade. The transition flow on blade surface has a great influence on heat transfer, and the calculation characteristics and the ability to predict transition flow of the four different turbulent models are obviously different.Compared to the three kinds of turbulent model, the shock-capturing properties of Transition k-kl-? model is stronger for the transonic flows, and the calculation results of temperature field and pressure field are consistent with the experimental results. The thermal stress analysis of the blade show that the predictive results of the temperature field of turbine blade has a significant influence on the thermal stress distribution. The thermal stress is the main factors influencing the strength of blade compared with the aerodynamic load stress, and the error of coupled heat transfer simulations has biased the structural strength of the blade much.With Transition k-kl-? model, the conjugate heat transfer fluid field simulation of the turbine guide vane has been calculated, and the data of the velocity field, pressure field,temperature field in three dimensional fluid field has been analyzed. The turbulence levels of inlet flow which can impact wall heat transfer, is one of the important factors affecting the cooling effect. Increasing turbulence levels can reduce the cooling effect, obviously in laminar flow area and transition area. Through the analysis of the cooling effect of different cooling gas flow, improving the flow rate of cooling gas is used to increase the cooling effect.The temperature load and aerodynamic load are loaded to the blade with finite element software, and the strength calculation and safety factors checking has been done, The results show that the improvement of boundary constraints is more reasonable, and the influence on Von Mises stress and total deformation of the temperature load is greater than aerodynamic load. Stress concentration region is noted at the tip and hub, and the strength of the blade structure design is basically consistent with the requirements of strength reservation.Increasing the flow rate of cooling gas can improve the safety factors of the blade within limits.