Effect of Orientation of Internal Turbulence Promoting Ribs on Flow Characteristics for Film Cooling

Journal of Thermal Science and Technology

Eiji SAKAI¹  Yukiko AGATA¹  Toshihiko TAKAHASHI¹  Koichi NISHINO² 

[1] Central Research Institute of Electric Power Industry;Department of Mechanical Engineering, Graduate School of Engineering, Yokohama National University;

关键词: gas turbine blade;    film cooling;    turbulence promoting rib;    rib orientation;    adiabatic film cooling effectiveness;   

DOI  :  10.1299/jtst.8.15

来源: DOAJ

【 摘 要 】

Numerical simulations have been performed to study the film cooling of a flat plate that has an internal cooling passage perpendicular to the main flow. The goal is to understand the effect of the orientation of turbulence promoting ribs installed in the internal cooling passage on the adiabatic film cooling effectiveness in the external main flow downstream of the cooling-air injection. Detached Eddy Simulation is carried out for the flow characteristics for two rib orientations at two blowing ratios. The simulation results have revealed that the rib orientation affects significantly the temperature and flow structures downstream of the cooling hole and therefore affects the film-cooling performance on the surface. The revealed difference is due to the presence/absence of intense spiral motion at the cooling-hole outlet and such a difference originates from an interaction between the flow separation behind the inclined rib and the flow suction at the inlet of inclined cooling hole. The simulation results are exploited to draw a clear picture for the fluid-dynamical mechanisms responsible for the effect of the rib orientation.

【 授权许可】

Unknown