Abstract: The inviscid-viscous interaction is used to analyze the three dimensional viscous flow in impellers in the present paper. The semi-orthogonal curvilinear coordinates, the anisotropy eddy viscosity turbulence model and Keller box method are used for calculating three dimensional boundary layers on blade surfaces. The direct nonlinear boundary element method is applied to calculate the three dimensional potential flow in impeller passage. Calculated results are found in agreement with measure values.

Key words: 边界层方程, 叶轮, 粘性流动