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在低速大尺寸压气机试验台上,利用体视粒子图像测速(SPIV)技术详细测量了不同气动负荷水平的叶片、不同转子叶尖间隙大小和不同工作状态时转子通道内部的流场结构。定量分析了不同测量条件下转子通道内堵塞分布特点,讨论了影响堵塞发展的物理机制,旨在为转子尖部流动控制和模化研究提供必要的理论帮助。结果表明:在本文的各种测量条件下,叶尖泄漏堵塞均呈现非线性、非单调性的特征,通常在叶片通道内出现堵塞峰值;叶片通道内的逆压梯度是堵塞增长的重要物理机制,在逆压梯度环境下,堵塞起始区域的流量越大,堵塞增长得越迅速,堵塞起始区域流体的总压损失越高,堵塞越容易引起失速;泄漏流与主流之间存在较强的湍流掺混,在这个物理过程中,黏性和湍流脉动所带来的主流与泄漏流之间的动能输运是使得堵塞衰减的主要物理机制。
In the low-speed and large-size compressor test bed, the structure of the flow field inside the rotor channel with different aerodynamic load levels, different rotor tip clearances and different operating states was measured in detail using stereo image particle velocity (SPIV) technique. The characteristics of blockage distribution in rotor channels under different measuring conditions were quantitatively analyzed. The physical mechanism of blockage development was discussed in order to provide the necessary theoretical help for the flow control and modeling of rotor tip. The results show that under various measurement conditions, the tip leakage occlusion shows nonlinear and non-monotonic characteristics, and the peak of plugging usually appears in the leaf channel. The reverse pressure gradient in the leaf channel is an important physical mechanism of the blockage growth In the reverse pressure gradient environment, the larger the flow rate in the initial area of plugging, the faster the plugging increase, the higher the total pressure loss of the fluid in the initial plugging area, the more easily the plugging causes the stall. The stronger the leakage flow and the mainstream In this physical process, kinetic energy transport between the main flow and the leakage flow caused by viscous and turbulent pulsations is the main physical mechanism that causes the blockage to decay.