对旋轴流风机叶顶形态对其性能的影响

为了探究改变叶顶结构对风机性能的影响,采用Fluent对不同叶顶形态的对旋轴流风机性能进行数值模拟。分析了不同叶顶形态对风机效率、全压、叶顶泄漏流和泄漏涡的影响。结果表明:风机效率随叶顶开槽长度的增加而增大。在开槽长度和深度相同时,与第一级叶轮相比,改变第二级叶轮的叶顶形态对风机性能的改善更加显著。与后缘相比,在叶顶前缘开槽对风机性能改善更大。叶顶开槽后,间隙处形成泄漏涡,且叶顶泄漏流入口处涡流强度明显提高,可有效削弱叶顶泄漏流的发展,改善风机性能。

Impact on Counter-rotating Axial Fan Performance of Blade Tip Geometry

This paper explores the effect of changing the blade tip structure on the performance of the fan. Firstly，the performance of the counter-rotating axial fan under different blade tip geometry is simulated with Fluent. Then we analyze the effects of different tip top morphology on fan efficiency, total pressure, the tip leakage flow and leakage vortex. Eventually, the results show that efficiency increases with the increasing of the length of the groove. Under the same groove length and depth, compared with the first stage impeller, changing the blade tip geometry of the second stage impeller has a more significant improvement on the performance of the fan. Slotting at the leading edge of the tip of the blade improves the performance of the fan more than the trailing edge. The leakage vortices are formed in the clearance after slotting on the top of the blade. And the vortex intensity at the tip of the tip leakage flow increases significantly. These can effectively weaken the development of tip leakage flow and improve fan performance.