摘要
为探索不等距布置叶片对一种微型风机气动噪声的影响,提出5种叶片分布方式进行性能和气动噪声性能分析。首先利用Realizable k-ε模型求解微型风机内部的非定常流动和性能,并获得声源项信息和风机出口压力脉动,最后采用FW-H方法预测风机出口的气动噪声。数值结果表明,叶片分布不均匀度较小时,分布方式对风机性能影响较小,过大则会引起全压和效率的下降;风机出口压力脉动和声压级有很强的相关性,叶片分布不均匀度在一定范围内可以降低压力脉动主频的幅值和声压级,但超过该范围,将会导致低于叶片通过频率的压力脉动幅值明显增加,该频率的声压级也随之增加。
In order to research the influence of blade distribution on the performance and the aerodynamic noise of a mini mixed flow fan, 5 kinds of blade distribution were designed based on the original fan. The unsteady flow and performance inner the mini fan is solved with Realizable k-a turbulence model in FLUENT software, and then sound source and outlet pressure pulsation is obtained, and finally aerodynamic noise was predicted by the method of FW-H. The result shows that the blade distribution affects the performance little when the level of unevenness is low, but high level will lead to the total head and efficiency＇ s drooping. And the pressure fluctuation has big relevance to aerodynamic noise in the exit of the impeller. The uniform blade can lower the amplitude of pressure fluctuation and sound pressure level （SPL） of blade passing frequency （BPF） in certain limits, but will increases SPL with frequency under BPF beyond the limit.
出处
《风机技术》
2015年第2期20-25,共6页
Chinese Journal of Turbomachinery
基金
浙江省健康智慧厨房系统集成重点实验室新型油烟机开发基金项目(N02014E10014)
