抄録
By visualizing the flow at the outlet cross section of the diffusers having the total divergence angle of 8° by tuft grid method, the flow patterns were examined. Due to the separated flow from the wall surface and corner parts, reverse flow occurred at the outlet cross section. With visualizing the near wall surface flow and the corner parts flow by tuft stick method, smoke tracer method and polystyrene tracer method, reverse flow patterns were examined. It was found that the revfrse flow were existent from outlet section to Inlet section at cornet section of regular pyramid diffuser.
