本文提出一种将蜂窝结构直接布置在涡轮动叶顶部的抑制涡轮径向间隙泄漏流动新措施,数值研究了有/无蜂窝叶对涡轮平面叶栅间隙泄漏流场的影响。结果表明,蜂窝叶顶使得进入蜂窝腔的间隙流体形成旋涡运动,对间隙流具有能量耗散的作用,形成的径向射流类似于"气动栅栏",增加间隙内流体的运动阻力,进而对间隙泄漏流产生有效的抑制效果。与常规无蜂窝平顶叶栅相比,蜂窝叶顶叶栅的相对泄漏流量减低了约10%,形成的泄漏涡尺寸减小,叶栅出口下游总损失降低了4%。
In this paper,a new strategy with regular honeycomb cavities applied on the tip of the rotor blades directly is proposed to suppress the tip clearance flow.Numerical simulation is performed to analyze the tip clearance flow in a highly-loaded turbine cascade with and without honeycomb tip.The results show that small scale of vortex rolled up in honeycomb cavities dissipates the energy of the tip clearance flow,meanwhile the radial jets in honeycomb cavities have a role of "pneumatic fence" to inhibit the leakage flow.Compared to the conventional cascade,the amount of leakage flow using inlet flow in honeycomb tip cascade reduce 10%.Besides,honeycomb tip gains smaller scale of leakage vortex,thus the leakage loss is decreased by nearly 4%.