仿生降噪蜗舌试验研究与数值模拟分析  

Practice and simulation analysis for reducing the centrifugal fan noise with bionics volute tongue

作　　者：孙少明[1,2] 任露泉[2] 梅涛[1] 张永智[3] 钱志辉[2] 

机构地区：[1]中国科学院合肥智能机械所,合肥230031 [2]吉林大学地面机械仿生技术教育部重点实验室,长春130022 [3]吉林大学机械科学与工程学院,长春130022

出　　处：《振动与冲击》2009年第5期32-34,共3页Journal of Vibration and Shock

基　　金：国家自然科学基金重点项目(50635030);国家985工程仿生科技创新平台建设项目;吉林省科技厅发展计划项目(2007546);吉林省产业技术研究与开发专项项目

摘　　要：利用逆向工程方法,提取长耳鸮翼表面形态与构型降噪特征元素,设计仿生降噪蜗舌。将仿生降噪蜗舌应用于离心风机气流噪声控制,通过对比试验研究,在整个频段的总声压级LA均低于原型风机,声压级平均降低2.3dB;影响仿生蜗舌降噪效果的主次因素为:仿生形态单元间距t、仿生形态单元个数n、仿生形态单元高度h。基于计算气动声学原理的数值模拟分析表明,仿生系统降噪机理主要为:减小了气流对蜗舌的冲击,使蜗舌表面紊流附面层压力脉动减弱并延缓蜗舌后部涡流分离脱落;使从风机叶轮流出的脉动气流在流经仿生蜗舌表面时,流速分布较为均匀,速度突变较少,气流稳定性的增强有利于降低气流噪声的产生。The long-eared owl wing surface with noise reduction characteristics is of remarkable influence on its flight noise.The features of its shape and configuration were analysed by use of the reverse restructure technology.Then the bionics volute tongue was designed to control the air current noise of the centrifugal fan.Through experimental study,it is found the bionics volute tongue reduces air noise of centrifugal fan in entire frequency band and the total acoustic pressure level LA is lower than that in the original case.The average sound pressure level decreases 2.3 dB.The primary and secondary influencial factors of bionics volute tongue on the noise reduction effect are:spacing between non-smooth units t,number of non-smooth units n and unit height h.The computer simulation indicates that,the noise reduction mechanism of bionics volute tongue surface shape mainly is:the impact of air current on the volute tongue is reduced;the pressure pulsation in the turbulent boundary layer on the volute tongue surface is weakened and the eddy shedding is delayed to fall off from the tail section of the volute tongue;the speed of pulsating air flow on the volute tongue surface which flows out from the impeller of air blower,becomes more evenly distributed and the sudden change of the speed reduces.The enhancement of flow stability is advantageous to reduce the noise production form the centrifugal fan air current.

关 键 词：仿生 蜗舌 噪声测试 离心风机 降噪机理分析 

分 类 号：TB17[生物学—生物工程]