叶尖小翼结合叶顶凹槽调控轴流压气机间隙流动的机理研究

The tip clearance flow dominates the behavior of the flow in the tip region and has a strong impact on pressure rise capability, compressor efficiency and stability. The influence of tip clearance flow manifests itself in two manners: a blockage that effectively reduces the pressure rise capability and loss that affects the efficiency of the compressor. Consequently, there is strong motivation to look for means to manage the compressor tip clearance flow to minimize its impact on performance. The influence of winglet-squealer tip on the behavior of compressor tip clearance flow will be investigated in this project by advanced experimental and simulation methods. During the investigation, the influencing factors and mechanism of winglet-squealer tip on the aerodynamic of compressor cascade, compressor rotor and compressor stage will be study, including the detail analysis of the size of tip clearance, inlet flow condition, geometrical parameters and configuration of the winglet-squealer tip. Based on these analyses, the interaction mechanism of tip leakage vortex, tip separation vortex, passage vortex, scraping vortex, horseshoe vortex, corner vortex and trailing edge vortex in compressor will be explored. And then, the causal link between tip leakage oscillation and rotating stall inception in compressor rotor with winglet-squealer tip will be clarified. Base on the above researches, the optimum rotor blade tip geometry will be given, which can lay the foundation for enhancing validity of winglet-squealer tip application in real compressor.

叶顶间隙流动带来的泄漏损失和堵塞效应，影响着压气机的压升能力、效率和工作稳定性，合理调控压气机叶顶间隙流动并降低其影响是提高压气机性能的有效措施。本研究拟采用先进的实验测量技术并结合数值模拟方法,针对叶尖小翼结合叶顶凹槽调控压气机叶尖复杂流动结构进行研究,深入探索和揭示叶尖小翼结合叶顶凹槽对压气机叶栅、压气机转子及压气机级气动性能的影响规律和作用机理。通过改变间隙尺寸、来流条件、小翼和凹槽几何形状及布局组合方式,研究以上诸因素的影响机理，并从流场结构入手，明晰叶尖泄漏涡、叶顶分离涡、通道涡、刮削涡、马蹄涡、壁角涡、尾缘涡等涡系之间的相互作用机制。揭示具有叶尖小翼及叶顶凹槽的转子中，叶尖泄漏涡非定常波动特征及其与转子失速先兆诱发机制的关系。研究过程的开展可以为获得最佳的压气机转子叶尖气动流型结构，提高叶尖小翼及叶顶凹槽技术在实际压气机中的应用奠定基础。

叶顶间隙流动带来的泄漏损失和堵塞效应，影响着压气机的压升能力、效率和工作稳定性，合理调控压气机叶顶间隙流动并降低其影响是提高压气机性能的有效措施。研究采用先进的实验测量技术并结合数值模拟手段,针对叶尖小翼结合叶顶凹槽调控压气机叶尖复杂流动结构进行了研究,深入探索和揭示了叶尖小翼结合叶顶凹槽对压气机叶栅、压气机转子及压气机级气动性能的影响规律和作用机理。通过改变间隙尺寸、来流条件、小翼和凹槽几何形状及布局方式,研究了以上诸因素的影响机理，并从流场结构入手，明晰了叶尖泄漏涡、叶顶分离涡、通道涡、刮削涡、马蹄涡、壁角涡、尾缘涡等涡系之间的作用机制。揭示了具有叶尖小翼及叶顶凹槽转子中，叶尖泄漏涡非定常波动特征及其与转子失速先兆诱发机制的关系。研究过程的开展为获得最佳的压气机转子叶尖气动流型结构，提高叶尖小翼及叶顶凹槽技术在实际压气机中的应用奠定了坚实基础。