不同直径及形状的短扰流柱群的流阻及换热

采用放大的模型对装有五排短扰流柱的涡轮叶片尾缘的冷却通道的流阻特性及通道端壁表面上的局部换热系数进行了测量 ,重点研究了扰流柱直径及形状的影响。结果表明 :(1 )扰流柱直径越大 ,压力损失系数越大。在相同条件下 ,圆柱形扰流柱排的压力损失系数要大于圆锥形扰流柱排的压力损失系数 ;(2 )圆柱形扰流柱排内的换热强化系数的增长速度比圆锥形扰流柱排要快 ,而且达到的最大值也较大。扰流柱直径越大 ,在相同的局部位置处换热强化系数越大 ;(3 )当扰流柱直径增加时 ,其阻力的上升要比换热的上升快的多。与圆柱形扰流柱相比 ,锥形扰流柱更有利于增强换热或减小流阻

Heat Transfer and Pressure Drop of Short Pin-Fin Array with Different Diameter and Shape

Measurements of heat transfer and pressure drop in the short pin fin array used in trail cooling channel of turbine blade have been performed.Effects of diameter and shape of pin on heat transfer and pressure drop were investigated.The results show that:(1) The pressure drop increases with the increase of diameter and the pressure drop of round pin fin array is greater than that of cone pin fin array.(2) The heat transfer on the endwall of round pin fin array channel is stronger as compared with that of cone pin fin array channel.(3) As diameter increases,the increase of pressure drop is faster than that of heat transfer and the ratio of heat transfer to pressure drop of cone pin fin array is larger than that of round pin fin array.