轴流风机结构优化设计及内部流动特性分析

针对如何提高便携式轴流风机的运行性能,通过对其结构进行优化设计,主要研究转子部件的叶片数及叶片安装角的改变对叶轮与导叶匹配性的影响.基于SST k-ω湍流模型,采用数值模拟探究其内部流动特性,并通过试验验证其可靠性.研究结果表明:叶片安装角对轴流风机性能影响较大,而叶片数的影响相对较小.通过对比分析不同模型间的内流特性,确定了适合便携式轴流风机的叶片安装角和叶片数;发现叶顶泄漏涡的发展对后导叶的影响随着安装角的变化存在不同,并诱发叶轮与导叶交界区域流体扰动,影响叶轮和导叶的匹配性;湍动能在叶轮叶片进口处存在最大值,叶顶区因叶顶泄漏,其湍动能相较与叶根区更大.便携轴流式风机结构优化和内部流动特性的分析对其设计具有一定的指导意义.

Structural optimization design and internal flow characteristics analysis of axial flow fan

Aiming at how to improve the operation performance of portable axial flow fan, through the optimization design of its structure, the effects of the number of blades of the rotor components and the change of the blade mounting angle on the matching of the impeller and the guide vane were mainly investigated. Based on the SST k-ω turbulence model, numerical simulations were applied to investigate its internal flow characteristics, and the reliability was verified by experiments. The results show that the blade mounting angle has a large influence on the performance of axial fan, while the number of blades has a relatively small effect. By comparing and analyzing the in-flow characteristics between different models, the blade mounting angle and blade number suitable for portable axial flow fan are determined. It was found that the development of tip leakage vortex has different effects on the near guide vane with the change of the installation angle and induces fluid disturbance at the junction region of the impeller and the guide vanes, which affects the matching of the impeller and the guide vanes. The maximum turbulent kinetic energy exists at the inlet of the impeller blades, and the top of the leaf region is greater than that in the root of the leaf region due to leaf top leakage. The analysis of the structural optimization and internal flow characteristics of axial fans in this paper has certain guiding significance for the design of axial fans.