EFFECTS OF END-WALL SHAPING ON STEAM TURBINE EFFICIENCY

摘要

this paper focuses on the effects of end-wall shaping of the guide blade in the steam turbine stages. The research of the effects of end-wall shaping on turbine efficiency has applied CFD numerical simulations and the measurement of straight blade cascades in the wind tunnel. The final stage of the research activities included experimental verification of the findings in an experimental steam turbine. As the findings have proven to be interesting in terms of efficiency, a series of 3D numerical simulations have been executed; these have demonstrated certain improvement when the shaping was used, especially in the blade tip area. The steam turbine has been used to measure the effects of shaping on both sides (bilateral shaping) as well as only in the blade tip area. The process has indicated efficiency improvement on blade tip shaping; however, this occurred only in partial admission. On the other hand, there has been a drop in efficiency compared to blades with straight end-walls.