Abstract In this paper,a 3D Euler solver and a direct problem code of S stream surface are applied to numerical analysis of the flow field in an annular stationary turbine cascade with bowed and twisted blades.Also,an experimental study on this cascade is made by blowing on an annular cascade test rig to verify the two calculation programs and to research the flow mechanism in the cascade.Numerical results show that the effect of blade bowing in circumferential direction is mainly reflected in the front of cascade and blade bowing has little influence on the flow beside blade pressure surface.After comparing the calculated results with the experimental data,it is found that in respect of circumferentially averaged flow parameters at the cascade exit,the 3D Euler solver is more precise in predicting the pressure distribution but less precise in predicting the flow angle distribution than the code of S stream surface.The experimental data verify the effect of blade bowing on the flow around blade hub,and show great losses occurring near blade tip due to excessive camber angle of blade profile and improper bowing of blade stacking line in that region.Some difference between the calculated results and the experimental data demonstrates that a more reasonable loss model and a more precise lag angle model should be worked out if a good design for turbine cascade with bowed and twisted blades is expected by means of an Euler solver or a throughflow code.
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