不同形式叶片前掠对轴流风机性能的影响

Effect of the different forms of blade forward stacking on the performance of axial-flow fan

主要基于CFD方法研究了不同形式的叶片前掠对轴流风机性能的影响。首先,对轴流风机进行了叶片前掠设计,提出了整体前掠和中部前掠两种叶片前掠方法。而后,基于数值模拟方法,对两种前掠形式的叶片与原型叶片进行了气动性能的计算和对比分析。最后,提取了叶轮流场的局部欧拉压头和叶片载荷,对叶片前掠的气动影响机理进行了分析。结果表明,叶片中部前掠可提高轴流风机叶轮设计流量点的气动性能,并保持全流量范围内较佳的气动性能;在设计流量点,叶片中部前掠使得轴流风机叶轮叶顶处的叶片载荷更趋集中于前部,有利于抑制叶轮的叶顶泄漏,进而提高风机的效率。

The effect of different forms of blade forward stacking on the performance of axial-flow fan is investigated by CFD method.Firstly,the blade forward stacking condition of an axial-flow fan is designed.Two forms of forward stacking blade,the forward overall-stacking blade and forward midstacking blade are proposed.Based on the numerical simulation method,the aerodynamic performance of these two forms of forward stacking blade and baseline blade is calculated and compared.The local Euler head(LEH)and blade loading in the flow field of impeller are extracted to reveal the mechanism of these effects of forward blade stacking on aerodynamic performance.The results show that,the blade forward mid-staking could improve the aerodynamic performance of axial-flow fan at the design flow rate and maintain that over the whole flow rate range.At the design flow rate,the blade forward mid-staking makes the blade loading at the impeller tip of axial-flow fan more concentrated in the front part,which is benefit to suppressing the tip leakage of impeller and improve the efficiency of fan.