叶片磨短对低压冷却风扇气动性能的影响  

Effects of blade cutting on the aerodynamic performance of low pressure cooling fans

作　　者：王巍雄[1] 李嵩[1] 黄东涛[1] 朱之墀[1] 朱克勤[1] 

机构地区：[1]清华大学航天航空学院工程力学系,北京100084

出　　处：《清华大学学报（自然科学版）》2007年第2期260-263,共4页Journal of Tsinghua University(Science and Technology)

摘　　要：工程中常用磨短叶片的方法来确保足够的叶顶间隙,由此对风扇气动性能的影响尚无研究报道。该文通过实验发现,叶片磨短后最大流量和风扇效率均急剧下降。对风扇内湍流场进行了三维数值模拟,结果与实验吻合良好。基于数值计算结果的流场分析表明,叶片磨短后叶顶间隙涡进一步发展,阻塞叶顶流道,使流量锐减,同时降低了叶片顶部区域做功能力。研究指出,叶片磨短相比机壳增大更易造成风扇性能恶化,尤其是流量的下降会使风扇无法正常使用,必须重视。Blade cutting is commonly used in fan design to maintain the required tip clearance but the effects on the fan performance are not well known. Experiments described in this paper indicate that blade cutting substantially reduces the maximum discharge and the fan efficiency. The simulated fan performance agrees well with the test data. The numerical results show that blade cutting causes the development of tip clearance vortices and blade passage blockages, which reduce the flow rate and the work done by the blade. Therefore, blade cutting causes more significant performance degradation than shroud enlarging, especially for the maximum discharge which may be reduced too much to be used in practice.

关 键 词：冷却风扇 数值模拟 叶顶间隙涡 

分 类 号：V231.3[航空宇航科学与技术—航空宇航推进理论与工程]