周向总温畸变下跨音压气机转子运行工况分析

Analysis of the Operational Condition of the Rotor Blade for a Transonic Compressor with Circumferential Total Temperature Distortion

进气总温畸变严重影响压气机稳定性,过去的研究往往把压气机整体作为研究对象,很少关注转子叶片在周期性转入转出畸变区时性能变化情况。本文以单级跨音压气机为研究对象,首先通过单通道定常计算开展均匀来流下的数值模拟,与试验数据对比验证了计算的准确性。然后开展了进口周向范围180°,高温500K的全环非定常模拟获得整条特性线,并分析了相比均匀来流条件下最高效率点的等熵效率增大的原因。最后详细介绍轨道法并利用该方法得到了最高效率点转子叶片在不同周向位置的压比-折合流量特性,发现总温畸变条件下,不同周向位置对转子载荷的影响基本等同于改变其折合转速,并分析得出最有可能先发生失速的周向位置是由低总温区转入高总温区时。

Total temperature distortion severely threats the safety of the compressor.Previous studies typically focus on the overall performance of the compressor,and how the working condition of a single rotor blade changes when it rotates across the distorted and undistorted region is less understood.In this study,steady simulations of a transonic compressor with clean inflow are conducted and validated with the experimental data.Thereafter,unsteady simulations with a 500 K,180°circumferential total temperature distortion are performed to obtain the distorted compressor characteristic.The distorted isentropic eficiency of the compressor is increased and the underlying mechanism is explained.In the last section,the orbit method is introduced and adopted to analyze the corrected mass fow and pressure ratio of the rotor at different circumferential positions.It is found that the effect of the total temperature distortion is the alternation of the rotational speed of the rotor.The rotor is most vulnerable when it just leaves the low total temperature region and enters the high total temperature region,where the stall can be initialized.