本文将叶顶微喷气方法应用于NASA Rotor37跨音速轴流压气机转子,在近失速工况,利用数值模拟方法研究了不同喷气量时叶顶间隙泄漏流对微喷气的非定常响应机理和叶顶微喷气的扩稳效果。结果表明,喷气使得叶顶区域的叶表压力随喷嘴与叶片相对位置的变化沿弦向发生波动,抑制了叶顶泄漏流的自激非定常波动,使叶顶泄漏流轨迹沿叶片吸力面向下游移动,实现了提高压气机性能和稳定性的目的。采用喷射气流的无量纲总动量可关联亚音速和跨音速轴流压气机不同喷气方案的扩稳效果,该无量纲总动量与来流总动量和喷射气流高度成反比,而与叶高和喷射气流总动量成正比。
Numerical simulation is utilized to investigate the response mechanism of unsteady tip leakage flow to discrete micro tip injection for the NASA transonic axial compressor Rotor37 at near stall operating point by varying injected mass flow rate. The effects of different injection schemes on stability enhancement are summarized and compared with the experimental results in open literatures. Injection mainly influences the rotor tip region. Under the influence of injected flow, the transient pressure distribution fluctuates along blade chord on both pressure and suction sides with respect to the relative position of injector and rotor. Thus, injection suppresses the self-induced tip leakage flow unsteadiness and shifts it trajectory without touching the neighboring pressure side meanwhile. So the improvement of compressor performance and stall margin can be obtained. The dimensionless total injected momentum can be used to scale the control effectiveness of different injection schemes for low or transonic axial compressors on a single curve, which is inversely proportional to the momentum of main incoming flow and height of injected flow, and direct proportional to the total injected momentum and blade height.