短扰流柱排端壁的平均换热实验

Experiments on heat transfer in trapezoidal channel with short pin-fin arrays

关键词:  涡轮叶片  扰流柱  换热  实验

Key words:  Turbine blade  Pin-fin  Heat transfer  Experimentation

摘要:

为了深入了解涡轮叶片尾缘扰流柱区域的端壁换热情况,针对梯形通道高稠度短扰流柱排,沿着弦向和径向都有出流或只沿径向出流的情况,通过实验测量了端壁换热分布,研究了弦向出流比(0.25～1)和弦向出流雷诺数(3×104～9×104)对端壁换热的影响。实验结果表明:(1)端壁平均努塞尔数随着雷诺数增加而增加,随着出流比的增加先下降,出流比从0.75到1平均努塞尔数又略增加。(2)不同出流比情况下,沿着弦向和径向努塞尔数的变化具有不同的规律。

Abstract:

An experiments study has been performed to investigate the heat transfer characteristics in trapezoidal channel with small spacing short pin-fin arrays.The effects of ratio of lateral-to-total flow rate(0.25c1) and flow Reynolds number(3×104Rec9×104) have been investigated.It is found that endwall averaged Nusselt number decreases with increasing ejection ratio c firstly,and then increases with increasing c as c>0.75.The results also show that Nusselt number distribution along chord-wise and span-wise directions is strongly dependent on the ejection ratio over the range of Reynolds number studied.