涡轮叶片吸力面气膜冷却效率的数值研究

Numerical investigation on film cooling effectiveness at suction surface of stator blade

针对某型导向叶片,运用RNG(renormalization group)湍流模型对涡轮叶栅通道内部的三维流场和叶片吸力面的冷却效率进行了数值模拟.分析在叶栅通道主流入口雷诺数Re=4×105～6×105和冷气吹风比M=0.5～3范围内,沿吸力面不同弦向位置处开设气膜孔对气膜冷却效率的影响.结果表明:各位置气膜孔单独喷射时叶片吸力面的冷却效率均随着入口雷诺数的增加而增大;在气膜孔出口下游附近,冷却效率随着吹风比的增加先升高后降低,在下游远处则一直随着吹风比的增加而增大;三个位置处气膜孔单独喷射时,位置1气膜孔的冷却效率较位置2和位置3的高.

The film cooling characteristics of blade surface were numerically investigated using the two-equation turbulence model of the renormalization group.Three-dimensional turbulent flow in turbine cascade and the cooling effectiveness on blade surface were studied under different Reynolds numbers and blowing ratios.The influence of the cooling effectiveness of cylindrical film cooling holes on the blade suction surface with varying location was investigated.Results show that the cooling effectiveness for each film cooling hole increases with the increment of the mainstream Reynolds numbers.The cooling effectiveness downstream the exit of holes changes obviously with the increment of blowing ratio,and away from the downstream the effectiveness keeps increasing with the increment of blowing ratio.Under the same condition the cooling effectiveness of location 1 was higher than other two locations.