Abstract：In order to explore the influence of the guide vanes on the flow characteristics of the injector, 7 different guide vane numbers and 5 different guide vane outlet angles were designed. In these schemes, the RNG k-ε and VOF models were used to numerically calculate the injector of the Pelton turbine considering the inlet of the elbow under rated conditions, and analyze the influence of the guide vane on the flow characteristics of the injector. The results show that the Dean vortex caused by the inlet elbow and the Karman vortex caused by the flow around the guide vanes always exist inside the injector and the jet region. The existence of these vortices causes the jet liquid surface to deform inside the elbow and downstream of the guide vane, and causes the jet diffusion. There are differences in the jet eccentricity of the injector with different numbers of guide vanes. The number of guide vanes increases, the phenomena of liquid surface bulge inside the jet and the jet diffusion are alleviated. However, the deformation of the corresponding area of the jet liquid surface downstream of the guide vane is more severe, which again affects the jet quality. The change of the outlet angle of the guide vanes has a certain influence on the stretched vortex caused by the guide vanes, but compared with the number of the guide vanes, the outlet angle of the guide vanes has less influence on the flow characteristics of the injector.
