Research of Numerical Flow Analysis for Pelton Turbine

In order to execute the flow analysis for Pelton turbine, the basic theory of space-time synchronous discretization for stationary and rotating frames is proposed based on unsteady vector triangle. By choosing the cross point of inner-most representative streamline of stationary jet with the locus of rotating splitter tip of bucket as the local origin of unsteady interaction, the position in tWO frames is connected by the unsteady vector triangle for space-time synchronous discretization. In any discrete cartoon frame in space and time, the changes of position in two frames are calculated by the unsteady displacement vector triangle and the shift between two frames is obtained successfully. The results of the flow analysis reveal that the unacceptable numerical interference in the water sheets can be a~oided by the unsteady frame shift between the stationary free jet and the rotating buckets, This analysis method provides a technical support to optimize the geometric design of Pelton´╝çs buckets by CFD.