| Film cooling technology is one of the most effective means of protecting the turbine blades. The compound angle jet are tilted toward not only the streamwise direction but also the blade height direction. The blades will be better protected by optimal control between compound angles and blowing ratio. It is very important for engineering designing to study the compound angle film cooling on turbine blades.First of all, Small-scale wind tunnel is built, and hot-film anemometer is used to measure the field of film cooling with a round hole at the jet injection angle of 90°in a flat plate and film cooling on leading edge of turbine blades. According to the flow velocity and turbulent kinetic energy distribution with different blowing ratio and the comparison between the experimental and numerical results for the different turbulence models in the same operating mode, some assumptions are made as follows:for the flat plate film cooling flow field, RNGκ-εmodel is more consistent with the experimental value, and for the blade film cooling flow field, Realizableκ-εmodel is closer to the experimental value.Second, the RNGκ-εmodel is adopted for the numerical simulation of the film cooling flows with a round hole at the jet injection angle of 30°,60°and 90°nd with compound angles jet with four different positions of holes-row in a flat plate. The results show that the maximum values of the film cooling effectiveness (η) and the Nusselt number (Nu) are found near the separation point of downstream side of the jet holes whatever the angle may be.ηand Nu decrease with increasing flow distance. The decrease is rapid when the blowing ratio is increased. The heat transfer effectiveness is highest with the angle of 30°, but the influence is weakest in the spanwise direction. Hole-rows with aligned arrangement have a very good film protection in the downstream zone more than ten hole-diameters. When the two rows are staggered at the half of the distance between adjacent holes, the cooling effectiveness is superior in the middle of two rows and in the downstream near-hole region less than ten hole-diameters.Realizableκ-εmodel is adopted to carry out the numerical simulation for film cooling flowing field of compound angles jet holes on leading edge of turbine blade and single angle jet holes on pressure surface and suction surface. The comparison of cooling effectiveness between 5 rows film holes and 8 rows film holes (including two projects) at different blowing ratio shows that the cooling effectiveness of every holes-row configuration is superior by increasing the blowing ratio. But 5 rows film holes is not cool enough to protect the turbine blades,8 rows film holes can form continuous film protective layer in the surface of blades. The cooling effectiveness of No.1 option of 8 rows is better than that of No.2 option.Finally, the large-eddy simulation (LES) is adopted to simulate film cooling flow field of a round hole with the angle of 90°in a flat plate and compound angles jet holes on leading edge of turbine blade when M=1.5. The results show that the complex vortex structure occurs near the cooling hole. The shedding cycle of jet hole vortex in leading edge is shorter than that of downstream. In pressure surface, Counter rotating vortex pair (CVP) is formed earlier than suction surface and the center position of CVP in pressure surface is more far away from the blade surface. It affects the effectiveness of the film protection.
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