仿鸮翼前缘蜗舌对多翼离心风机气动性能和噪声的影响

Effects of Bionic Volute Tongue Bioinspired by Leading Edge of Owl Wing on Aerodynamic Performance and Noise of Multi-Blade Centrifugal Fan

针对某多翼离心风机,受鸮类翅膀前缘结构的启发,设计了一种新型降噪结构——仿鸮翼前缘蜗舌。基于逆向工程方法,通过提取长耳鸮翅膀气动性能较好的40%翼展方向上的翅膀剖面型线,对风机蜗舌进行了仿生降噪重构设计,并分别对原型风机和仿生蜗舌风机的气动性能和噪声特性进行了数值模拟。研究结果显示,仿鸮翼前缘蜗舌风机的风量较原型风机增加了1.9m3/min,噪声下降了1.6dB,效率提高了3.8%,表明采用仿生蜗舌有效降低了气流对风机蜗舌的冲击作用,抑制了流动分离的发生,在蜗舌附近区域流场的逆压梯度明显减小,涡的结构、强度和分布都有所改变。

Bionic volute tongue bioinspired by the leading edge of owl wing, a new type of noisereduction structure, is designed for multi-blade centrifugal fan. Adopting reverse engineering method, the section profile in the position of 40% spanwise of the wing of a long-eared owl, whose aerodynamic performance is relatively excellent, is extracted to restructure the bionic volute tongue. Numerical simulations are respectively conducted to investigate the aerodynamic performance and noise characteristics of the prototypical fan and the developed fan with the bionic volute tongue. Compared with the prototypical fan, the volume flow rate of the bionic fan is increased by 1.9 m^3/min, while the noise is decreased by 1.6 dB and the efficiency is increased by 3.8%. The bionic volute tongue bioinspired by the leading edge of owl wing facilitates weakening the impact of the airflow to the volute tongue of multi-blade centrifugal fan, and the flow separation is suppressed effectively. Near the volute tongue, the adverse pressure gradient is reduced significantly, and the corresponding vortex＇s structure, distribution and intension are also changed.