紊动射流对叶栅内气相流场的影响

Study of Turbulent Air-Cushion-Cascade

从空气动力学的角度提出了“气垫防磨”理论 ,并以气垫叶栅作为研究对象 ,在不同的主流与射流速度比、不同的缝隙数和缝隙宽度等条件下 ,利用IFA30 0型热膜风速仪系统对叶片表面附近的流场进行了测量 ,得出了各工况下的气垫厚度 .结果表明 ,增加射流速度、缝隙宽度和缝隙数量 ,气垫厚度也相应增加 ,并且气垫的厚度主要由叶片前半部分的射流决定 .在理论上论证了气垫防磨的可行性 .

Experimental and numerical studies of air-cushion-cascade were presented. The experiment was done by IFA 300 aerometer. The flow field was measured for different main-stream to jet velocity ratios, different number of gaps and a couple of gap width. The contour of the air-cushion was obtained, and the numerical calculations gave a close result. It was shown that air-cushion thickness would increased with the increasing of the jet velocity, gap width and gap number, and air-cushion thickness mainly was determined by the jet in the former half cascade. The possibility to achieve anti-erosion by the turbulent jet was theoretically demonstrated.