等离子体气动激励改善气膜冷却效率的数值研究

为了获得等离子体气动激励改善气膜冷却效率的机理及影响规律,采用数值模拟方法研究了等离子体气动激励电极相对位置x/L分别为0.3、0.4和0.5时不同吹风比下的流动过程和冷却效率的分布情况,并通过与常规气膜孔冷却结构形式进行的对比,以揭示等离子体气动激励改善气膜冷却效率的作用机理。研究表明:等离子体气动激励产生的等离子体流能诱导冷却气流偏转,使冷却气流更好地贴覆壁面,改善了气膜冷却效率;等离子体气动激励电极位置离气膜孔出口距离越近,等离子体流诱导改善气膜冷却效率的作用越好,并且随着吹风比的减小,其作用效果越明显。

Numerical Investigation on Improvement of Film Cooling Efficiency with the plasma actuation

To investigate the influence of plasma actuation on film cooling efficiency,a numerical study of the distributions of the flow fields and cooling efficiency is employed with different placement of plasma actuation pole in several ratios.And their distributions are compared with the distributions of baseline holes to reveal the good effects of the plasma actuation on the film cooling performance.The results show that the plasma actuation can attract the cooling flow to form better coverage on the hot side,thus improving the film cooling efficiency.The improvement of the film cooling efficiency is significant at lower blowing ratio with shorter distance between the plasma actuation pole and the outlet of film hole.