摘要
采用数值模拟的方法,对比研究了不同环量指数的轴流风扇在设计工况下的气动性能,通过分析风扇内部流动结构,揭示了沿叶高变环量设计对气动性能影响的控制机理。结果表明:环量指数取适当的负值时,风扇叶顶通流能力较强,削弱了间隙处逆流对主流的影响,减小叶顶间隙泄漏带来的损失;但环量指数若取值过小,会使吸力面根部沿径向指向叶顶和沿轴向指向前缘的静压梯度较大,促进了附面层的分离,增大了二次流动损失。本文的轴流风扇在环量指数取-0.2左右时气动性能最好。
In the present paper, the aerodynamic performance of axial flow fan with different circulation index at a design flow rate is shown, and the internal flow characteristics is also discussed and analyzed by numerical simulation method. Results indicate that when circulation index takes an appropriate negative value, the stronger flow capacity of blade tip could weaken the influence of gap reflux on the mainstream, reducing the tip leakage loss, but if the value of circulation index is too small, it will exist larger static pressure gradient on suction surface in blade root which points to the blade tip along the radial and points to the leading edge along the axial direction, prompting the boundary layer separation, increasing the secondary flow loss. When circulation index takes-0.2, the axial flow fan makes its best .aerodynamic performance.
出处
《风机技术》
2012年第4期23-27,38,共6页
Chinese Journal of Turbomachinery
关键词
轴流风扇
变环量设计
扭叶片
气动性能
叶顶间隙
axial circulation design
flow fan
variable twisted blade
aerodynamic performance
tip clearance
