Effects of the Inlet Boundary Layer Thickness and the Boundary Layer Fence on the Heat Transfer Chracteristics in a Turbine Cascade

입구경계층 두께와 경계층 펜스가 터빈 캐스케이드내 열전달 특서에 미치는 영향

  • Published : 2001.06.27


The objective of the present study is to investigate the effects of the various inlet boundary layer thickness on convective heat transfer distribution in a turbine cascade endwall and blade suction surface. In addition, the proper height of the boundary layer fences for various inlet boundary layer thickness were applied to turbine cascade endwall in order to reduce the secondary flow, and to verify its influence on the heat transfer process within the turbine cascade. Convective heat transfer distributions on the experimental regions were measured by the image processing system. The results show that heat transfer coefficients on the blade suction surface were increased with an augmentation of inlet boundary layer thickness. However, in a turbine cascade endwall, magnitude of heat transfer coefficients did not change with variation of inlet boundary layer thickness. The results also present that the boundary layer fence is effective in reducing heat transfer on the suction surface. On the other hand, in the endwall region, boundary layer fence brought about the subsidiary heat transfer increment.