A three- dimensional steady N- S equation was discretized by volume- control method to simulate the effects of hole shapes on cooling effectiveness of turbine blade in combining with two- layer k - e turbulence model. A cylindrical hole and a fan shaped hole with laid- back were adopted,and the flow-field near the cooling hole and the blade is obtained. The results show the fan shaped hole with laid- back decreases the ratio of the momentum of the ejection flow, reduces the capacity of the ejection to pass through the main flow, and produces a velocity component along the span wise direction, resulting a better film recovery on the blade wall. The cooling effectiveness of the turbine blade adopted by a fan shaped hole with laid- back is superior to the blade with a cylindrical hole along the span wise and stream wise direction.%基于有限体积法对三维定常N-S方程进行离散,采用k-ε两方程湍流模型,数值研究了气膜孔几何形状对涡轮叶片气膜冷却效果的影响,得到了气膜孔附近的流场分布.所选孔形为圆柱孔和后倾扇形孔.结果表明后倾扇形孔减小射流动量比,减弱射流穿透主流的能力,并产生了一定的展向速度,可使射流冷气能够较好地贴附在壁面上起到保护作用.具有后倾扇形孔的涡轮叶栅沿叶高方向和流线方向体现出了比圆柱形冷却孔更好的冷却效果.
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