微型轴流风扇叶顶间隙内泄漏流动的数值模拟

Analysis of Microminiature Axial Tip Clearance Fluid

运用FLUENT软件对一种微型轴流风扇内部的非粘性三维流场进行数值模拟,获得了风机内部叶顶间隙内流动规律。对叶顶间隙泄漏涡流的形成和发展作出了比较详细的分析,得到随叶尖间隙的增大,泄漏流动形成泄漏涡,旋涡强度随叶顶间隙的增大(从0.5 mm增大到6 mm)迅速增大到最大值,之后叶顶间隙继续增大,泄漏涡范围增大,但强度不再继续增大。经分析还得到叶顶间隙涡产生于吸力面近叶顶区域,并朝相同流道叶片的吸力面向尾缘方向发展。其结论为进一步弄清叶顶泄漏涡流的流动机理以及为微小型轴流风扇的优化设计都提供了依据。

Numerical simulation is carried out on axial fan internal non-viscous 3D fluid using commercial CFD software. Some important detailed fluid and regular patters are obtained. The generation and development of the tip leakage vortex are analyzed in detail. The conclusion is that with the augment of blade tip clearance the leakage vortex forms for the leakage flow, when the clearance between tip fans enlarges from 0. 5 mm to 6 mm the intensity of the vortex up to the maximum value increasingly, and then the range of leakage vortex continue to extend with the augmentation of the clearance but the intensity not. Another conclusion is that the tip leakage vortex generates from the blade suction side close to tip and develops from the suction side of blade with same flow runner to the caudal edge. It can provide basis for studying the fluid principle of the tip leakage vortex and the optimum design of mierominiature axial fan.