某变循环发动机超声涡轮设计与分析

应用相似理论原理,为某变循环发动机在高、低涵道比两种工作模式下设计了高膨胀比、大焓降超声高压涡轮,叶片造型采用S₁流面三维造型法实现.通过三维数值模拟对设计涡轮在以上两种工作模式下进行了验算,应用Spalart-Allmaras一方程湍流模型求解雷诺平均Navier-Stokes方程,并引入Abu-Ghanam Shaw转捩模型描述叶片表面边界层发展过程.数值模拟结果表明,涡轮在两种工作模式下等熵效率分别达到92.79%和92.31%,优于设计预期;三维造型法考虑了S1流面的物理特征,是一种精确而有效的叶片造型方法. 

Design and analysis of HP-turbine for variable cycle engine

A supersonic highly loaded high-pressure turbine with large enthalpy drop was designed for a variable cycle engine(VCE) in two operating modes of high and low bypass ratio by using similarity principle,and the blade profiles were implemented by means of a new three-dimensional(3-D) profile design method based on S1 stream surface.Then,3-D numerical simulations were performed for the turbine in both operating modes under different thermodynamic cycle parameters to confirm the design methods and results.One-equation turbulence model of Spalart-Allmaras was applied to solve Reynolds averaged Navier-Stokes equations,whilst the transition model of Abu-Ghanam Shaw was introduced into the calculations to capture the development process of boundary layer on blade surface.The results of simulations indicate that excellent aerodynamic performances are available in both operating modes with overall efficiency of 92.79% and 92.31%,respectively,which are superior to anticipated targets;the used profile design method by S₁ stream surface is more precise and effective than conventional cylinder method for turbine blade,since 3-D characteristics of flow fields are considered elaborately.