气膜冷却孔几何结构对流量系数的影响

Influence of geometrical construction of film cooling hole on discharge coefficient

为了研究火焰筒壁面气膜冷却孔几何结构对流量系数的影响规律,设计了几种具有不同几何尺寸和排列结构的气膜冷却孔实验件。对气膜冷却孔的流量系数进行了实验研究。实验结果表明,在吹风比较小时,随吹风比的增加流量系数大幅度增加,当吹风比较大时,随吹风比的增加流量系数增幅减小。同时,在气膜孔厚径比大于1时,气膜孔的排列形式对流量系数的影响不大,当厚径比小于1时,叉排气膜孔的流量系数要高于顺排气膜孔的流量系数。

In order to study the influence of dimensional configuration of the film cooling hole on the discharge coefficient, some kinds of fihn cooling holes with different dimensional configuration were designed. The discharge coefficient characteristics were all studied by the experiment. The results showed that the discharge coefficient of film cooling hole was greatly increased with the increase of blow ratio when the blow ratio M is lower, buta it had a little increase with the increase of M when M is larger. At the same time, when the thickness-diameter ratio was larger than 1, it has little influence on the discharge coefficient for the hole configuration, but when the thickness-diameter ratio was less than 1, the discharge coefficient of the hole with across arrangement is higher than that with sequence arrangement.