逆向涡流发生器可以有效减小涡轮叶尖泄漏流,提高叶片周向载荷。对影响逆向涡流器减小泄漏流的几个关键因素进行了数值研究,结果表明:入流和出流孔径比增大,涡流器流量增加,对叶尖泄漏流的减小效果越好,孔径比2∶1时比孔径比1∶1时涡流器流量增加了24%,叶尖泄漏流量降低了0.8%,叶片周向载荷提高了1%;与叶片前缘布置涡流器相比,在叶片中后部布置时涡流器流量增大,叶片周向载荷提高;涡流器布置越密,涡流器总流量增加,布置33个涡流器比布置9个涡流器叶尖泄漏流量降低了1.6%,叶片周向载荷提高了2.7%;出流角越小,叶尖泄漏流量越小,叶片周向载荷越大,出流角30°时泄漏流量比60°时降低了1.2%,叶片周向载荷提高了约2%。
Backward vortex generators(BVGs) can reduce tip clearance leakage flow of the turbine and increase the circumferential load of the blade.Numerical study of several key factors of BVGs for reducing leakage flow is done.Results show that the mass of BVGs increases as the diameter ratio of the inflow and outflow holes grows,with more leakage flow reduced.Compared with the ratio of one,the mass of the BVGs increases by 24% and the mass of the leakage flow decreases by 0.8%,accompanied by 1% improvement of the circumferential load for the ratio of two.When BVGs are arranged in the middle and the rear parts of the blade tip,the mass of BVGs and circumferential load of blade increase,comparing with BVGs arranged in the front part.When the number of BVGs grows,total mass of BVGs increases.In the only 9 BVGs case,the mass of the leakage flow decreases by 1.6% and the circumferential load improves by 2.7% for the case of 33 BVGs.As the outflow angle becomes smaller,the mass of leakage flow decreases,thus improving the circumferential load.For 30° outflow angle,the mass of the leakage flow decreases by 1.2% and the circumferential load increases about 2%,comparing with 60° outflow angle.