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应用高雷诺数ｋ－ε湍流模型进行了混流式风机叶轮内三维流动的计算研究．使用ＳＩＭＰＬＥ型算法求解了全三维雷诺平均质量加权Ｎ－Ｓ方程．对流项采用了高阶精度的上流加权近似和ＴＶＤ类型的ＭＵＳＣＬ差分格式．采用非正交贴体坐标和同位网格系，速度的协变物理分量被选作为独立求解变量．为了消除非物理的压力和速度振荡，对界面上的逆变速度分量采用Ｒｈｉｅ、Ｃｈｏｗ动量插值方法．离散方程以能够使用三对角矩阵算法的形式书写，并用ＡＤＩ方法求解．求解中考虑了周期边界条件和运动壁面边界条件．文中给出了２个混流叶轮的计算结果．１号叶轮采用常规的设计方法进行设计．２号叶轮采用新型的弯扭组合三元叶轮设计方法进行设计，以消除和抑制叶轮叶道内和叶轮后无叶间隙处的气流分离和旋涡．计算结果表明，全三维湍流计算能有效地预测混流叶轮叶道内及无叶间隙处的分离，以便改进气动设计、几何设计，提高混流式风机的性能．
The high-Reynolds number k-ε turbulence model was used to calculate the three-dimensional flow in Francis turbine impellers. The SIMPLE algorithm is used to solve the full three-dimensional Renault mean-mass weighted N-S equation. The convection term uses a high-order weighted high-power weighted approximation and a TVD-type MUSCL difference scheme. With non-orthogonal body coordinates and co-mesh systems, the covariate physical components of velocity are chosen as independent variables. In order to eliminate non-physical pressure and velocity oscillations, Rhie, Chow momentum interpolation method is applied to the velocity components in the interface. Discrete equations can be written in a form that can be used using a tridiagonal matrix algorithm and solved using the ADI method. The solution takes into account the periodic boundary conditions and the moving wall boundary conditions. The paper gives the calculation results of two mixed flow impellers. Impeller No. 1 is designed using conventional design methods. The No. 2 impeller is designed with a new design method of the combination of the three-way impeller with a combination of bending and torsion to eliminate and suppress the airflow separation and the vortex at the non-leaf clearance in the impeller and the impeller. The calculation results show that the full 3D turbulence calculation can effectively predict the separation of the inside and non-leaf clearance of the mixed impeller in order to improve the aerodynamic design and geometric design and improve the performance of the Francis fan.