摘要
轴流风机尾缘涡脱落是产生噪声的重要因素,为改善尾迹流动来降低风机噪声,通过在轴流风机尾缘添加一种正弦形锯齿结构,采用定常及非定常数值模拟的手段结合实验验证的方式,分析其对轴流风机尾迹和气动性能的影响。研究结果显示,正弦锯齿结构削弱了叶片尾缘做功能力,使得风机全压降低,但提升了中小流量工况下风机效率;并能减弱叶片中部以下位置的尾迹强度,且对尾迹的抑制作用从叶片部底到中部逐渐减弱;以增加转速的方式补偿锯齿结构引起的压损,对原型风机和提升转速后的尾缘锯齿结构风机在设计流量点进行噪声数值预测分析,结果显示低频段噪声比原型机有明显改善,表明这种尾缘正弦形锯齿结构一定程度上是一种抑制轴流风机低频噪声的有效途径。
Vortex shedding at the location of trailing edge of the axial fan is an important factor to generate noise. Aiming at ameliorating the wake flow to decrease noise, a sinusoidal sawtooth structure was added to the trailing edge of the axial fan. The effects of the wake and the aerodynamic performance of the axial fan are studied by means of steady and unsteady numerical simulation combined with the experimental verification. The results indicate that the sinusoidal sawtooth structure weakens the power ability of the trailing edge of the blades, which reduces the total pressure of the fan, but enhances the efficiency of the fan under the small and medium flow rate conditions.Meanwhile, it can weaken the wake strength at the lower part of the blade, and the restraining effect on the wake was gradually weakened from the bottom to the middle of the blade. For the purpose of compensation for power capability losses due to serrated trailing edge, numerical predictions about noise on prototype and modified model which operate under higher rotor speed have been both calculated. It is argued that the sinusoidal serrated trailing edge structure has positive effects on reducing low frequency noise. Thus, it can be inferred that this kind of trailing edge with sinusoidal sawtooth structure is an effective way to restrain the low frequency noise of axial fan to a certain extent.
作者
唐俊
王军
隽智辉
刘辉
吴兰勇
TANG Jun WANG Jun JUAN Zhi-Hui LIU Hui WU Lan-Yong(School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China Guangdong Nedfon Indoor Air system Technology Co.,ltd, Taishan 529200, China)
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2017年第10期2145-2150,共6页
Journal of Engineering Thermophysics
基金
国家自然科学基金(No.51376077)
中国南方智谷引进创新团队项目(No.2013CXTD01)
关键词
正弦锯齿尾缘
轴流风机
尾迹
噪声
sinusoidal serrated trailing edge
axial fan
wake
noise
