CFD Simulation of Film Cooling flow

Abstract

This study is a two-dimensional numerical investigation of the effectiveness of film cooling for a turbine blade leading-edge model with a single cooling configuration. The model consists of a half cylinder with a flat after-body. Multi-block grids were generated using ICEM, and the flows were simulated using the flow solver Fluent. Simulations were carried out for Blowing ratios, B.R, ranging from 0.75 to 2.0. Turbulence was modeled using the k-ω shear-stress transport (SST) model. The values obtained for effectiveness were far from those obtained by experimental investigation due to the absence of the span wise averaging but still agrees with the findings B.R=1 gives the highest film cooling effectiveness .Also the concept of pulsing the coolant flow was Implemented so as to achieve film-cooling effectiveness equivalent to that with constant cooling, but with reduced overall coolant air, thereby enhancing turbine efficiency. Pulsed Cooling with pulsing frequency PF = 10Hz, and duty cycle DC = 50% was investigated and after time averaging it shows the exact same behavior as the continuous flow. Two other angles (20°, 24°) were investigated the 21.5° coolant shows better film cooling effectiveness