Investigation Of Transonic Fan Corner Stall Modeling Design And Non-axisymmetric End-wall Contouring

In order to simplify the experimental study of the improvement on corner flow in transonic fan by applying non-axisymmetric end wall.Modelling design of corner flow was studied firstly and the modeling similarity criterion was defined.The similarity between the experimental model and the fan corner flow field was achieved by the design of blade profile parameters.Based on this model,numerical optimization method was used to design the non-axisymmetric end wall and its influence on the flow field was analyzed under multiple working conditions.Finally,the end wall was applied to the fan hub to analyze its control effect on the flow separation in the fan corner region.The results show that after using the cascade modelling method,corner separation flow and characteristics of blade load of cascade are similar with fan.Profiled end wall can delay the development of channel vortex and transfer the low-energy fluid to the main flow area.And the scale of vortex near end wall is reduced thus make outlet flow more uniform.The ability of reducing loss is increased when inlet flow is negative incidence.Effectiveness of controlling corner flow of transonic fan is also presented and similar with cascade when under design condition and negative incidence.The area with high loss coefficient is decreased and the accumulation of low-energy fluid near the corner region is reduced.Outlet flow is more uniform,thus improves the matching with compressor.