动叶端区控制体分析方法在跨音轴流压气机周向槽机匣处理中的应用

The Control Volume Analysis of the Rotor Tip Region and its Application in Circumferential Grooves for Transonic Axial Compressors

本文从实际应用角度出发,提出了一种基于三维数值模拟的分析方法,可用于快速比较不同轴流压气机周向槽机匣的扩稳能力。在对失速机理是主流/泄漏流交界面在前缘溢出的认识基础上,确定了以动叶端区轴向动量作为衡量不同周向槽方案对压气机稳定性影响的特征量。不需对机匣处理计算到失速点,仅在光壁失速点流量下,通过比较端区轴向动量的分布即可预测不同方案的扩稳能力。进而以某跨音速转子为示例,分析预测了其七种不同周向槽方案的扩稳能力并利用实验验证了这一方法的预测结果。

A novel control volume approach is developed aiming at assessing the circumferential grooves effectiveness on stability improvement.The underlying mechanism for this approach is based on the hypothesis that the spike stall precursors can be triggered by the forward spillage of the rotor tip leakage flow and the onset condition of such a spillage is determined by the axial momentum balance within the rotor tip region.Control volumes are defined to quantify the axial momentum balance of the whole region that groove influenced in the rotor tip.The distribution curve of the cumulated axial momentum along the axial chord is proposed to assess the different grooved casings.As an example,multiple-groove configurations for a transonic rotor are analyzed.The experimental results verified the predictions by this approach very well.