Investigation On The Characteristics Of Leading Edge Film Cooling Of Turbine Blade

The increasing of the turbine inlet gas temperature is good to the thrust and thermal effectiveness of aero engine. Since 1960 s, the turbine inlet temperature has been improved, which has been beyond their limit of the capacity of blade material. The leading edge region of turbine blade is directly covered with high temperature gas, and at which the peak value is located, hence cooling measure in this areas is needful.In this study, film cooling on the blade leading edge was investigated numerically and experimentally. The effect of hole shape and location on the blade surface heat transfer characteristics was also researched. Data obtained in this study can guide the future optimization of turbine blade cooling. Specific contents are shown as follows:(1)The surface cooling effectiveness and convective heat transfer coefficient were investigated experimentally. The effect of hole shape and location on the blade surface was concluded. The research result shows that : as increasing of the blowing ratio, the cooling effectiveness and heat transfer coefficient increase. The cooling effectiveness and heat transfer coefficient reach maximum outlet the hole, then decrease along the flow direction because the film become more weaker. The minimum value is located at the trailing edge of the blade. The cooling effectiveness and convective heat transfer coefficient of the suction surface is higher than the pressure surface with the same blowing ratio when the suction surface and the pressure surface of the blade leading edge are simultaneously provided with film holes. In the film outlet zone,the cooling effectiveness and convection heat transfer coefficient of cross hole is higher than the circular hole.(2)The software Fluent was used to simulate the film cooling characteristics under the practical working condition. The influence of leading edge film cooling holes was researched. Hole shape and position was considered as well. At the same time, certain typical experimental data were chosen to compare with the numerical simulation. The experimental results are in good agreement with numerical simulation.