气膜冷却涡轮数值仿真技术进展

Progress of Film-cooling Turbine Numerical Simulation Technology

随着航空发动机性能的不断提高,高压涡轮进口燃气温度不断提升,远远超过了金属许用温度。为了安全运行,需要对涡轮进行冷却。由于气膜冷却具有冷却效率高、易于实现等优点,在航空发动机中得到了广泛的应用。但由于用于气膜冷却的空气流量大、且与主流掺混过程复杂,如何准确模拟冷气与主流的掺混是气冷涡轮的设计关键。本文对气膜冷却涡轮仿真采用的冷气喷射源项法和真实气膜孔仿真方法的国内外发展及现状进行了阐述,总结了两种方法的优缺点和工程应用情况,并从工程应用角度对下一步的研究方向提出了建议。

Inlet gas temperature of the high pressure turbine is increasing as aircraft engine performance improving, which is much higher than metal endurable temperature. So cooling technology is used in turbine for working safety. Film-cooling, with high cooling efficiency and easy realization, is widely applied in aircraft engines. However, for the usage of large mass flow cooling air and the complexity of mixing with main gas flow, how to simulate the mixing process become a key step of design in cooling turbine. In this paper, the developments of source term method and real film hole method were expatiated, the two methods were widely used in film-cooling turbine aerodynamic simulation. The advantages, disadvantages and engineering application status of the two methods were summarized, and the next research directions in engineering application were suggested.