跨音压气机转子近失速工况叶尖非定常流动分析

对跨音压气机Rotor35进行单通道全三维定常/非定常数值模拟,并与试验总性能和流场分布对比校核了数值计算精度。以此为基础开展的近失速工况点的非定常计算发现,来自相邻叶片通道未形成泄漏涡的间隙泄漏流体与来流、激波与泄漏涡干涉形成的低能破碎区相互作用形成了叶尖二次涡。叶尖二次涡向下游运动过程中,其所处的位置和产生的阻塞影响了近叶顶载荷的分布,最终使得叶尖部流场出现了循环往复的自维持的非定常波动现象。

Analysis of Near-Tip Unsteady FlowField in a Transonic Compressor Rotor at Near Stall Condition

Three-dimensional single-passage steady and unsteady simulations were carried out to investigate the flowfield in a transonic compressor rotor(Rotor 35).Via comparing the steady predicted results with the available experimental data,it turned out that,in addition to matching the total performance map well,the predicted results also captured the trend of development of tip leakage vortex(TLV) reasonably well.The further unsteady calculation at near stall condition showed that the tip leakage flow without rolling up into TLV,encountered the incoming flow and then interacted with the low-energy area due to the breakdown of TLV.thus leading to the formation of tip secondary vortex(TSV).With the rearward movement of TSV,its location and associated blockage resulted in cyclic variation in near-tip blade loading,which in turn lead to the.occurrence of a periodic self-sustained unsteady flow phenomenon in near-tip passage.