立式管道泵流动噪声特性与仿生降噪研究  

Flow Noise of Pipeline Pump and Bionic Sound Optimization

作　　者：张金凤[1] 贾静 胡日新 王洋[1] 曹璞钰[1] ZHANG Jinfeng;JIA Jing;HU Rixin;WANG Yang;CAO Puyu(Research Center of Fluid Machinery Engineering and Technology,Jiangsu University,Zhenjiang 212013,China)

机构地区：[1]江苏大学流体机械工程技术研究中心,镇江212013

出　　处：《农业机械学报》2018年第9期138-145,共8页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金项目(51379091);江苏高校优势学科建设工程项目(PAPD)

摘　　要：为了研究立式管道泵内部声场特性,减少管道泵运行时的噪声,基于CFD+Lighthill声类比理论对管道泵内部流场与声场进行仿真求解,并借鉴猫头鹰羽毛端部锯齿结构进行仿生优化,以期达到降噪目标。针对0.8Qd、Qd及1.2Qd3个运行工况,选用RNG k-ε模型分别对立式管道泵进行非定常数值模拟,获得3个工况下管道泵内部压力脉动数据。提取非定常计算所得的脉动力,导入声学软件LMS Virtual.lab中进行声场计算,得到各工况下管道泵进、出口声压级、泵体内部的声压分布及主要噪声源分布。结果表明:管道泵内部流动诱导噪声与压力脉动密切相关,主要是由叶轮与泵体的动静干涉引起,其频率特性与压力脉动相似,声压分布集中在轴频、叶频及其倍频,叶频时声压级最大。流量越大,管道泵进、出口声压级越大。基于仿生学原理,参考猫头鹰体表覆羽样本利用相似准则设计仿生锯齿叶片,展开仿生降噪研究,选择齿距、齿宽、齿高3个因素,设计了16组正交试验模型,计算得到各工况下泵内部流场和声场数据。选取最优降噪模型与原模型进行对比分析,结果表明:仿生叶片尾缘锯齿结构能够起到降低压力脉动、稳定流场、降低噪声的作用,其中设计工况下噪声降幅明显,叶频处噪声降低8 d B。In order to research the internal sound field characteristics and reduce the running noise of vertical pipeline pump,the CFD and Lighthill sound analogy theory was adopted to solve the internal flow and acoustic field. The sawtooth structure of the owl feather was used to conduct bionic optimization to reduce noise. Firstly,the pressure fluctuation of pipeline pump at 0. 8 Qd,Qdand 1. 2 Qdwere obtained from the unsteady simulation with the RNG k-ε turbulence model in CFX software. The datum of pressure fluctuation were extracted and input into the LMS Virtual. lab acoustics software,the SPL of the pump discharge,internal sound pressure distribution and main noise source in pumps at different flows were got by acoustic field calculation. The simulation results showed that the flow-induced noise of pipeline pump was closely related to the pressure fluctuation which was mainly caused by rotor-stator interaction,both of them had the same frequency characteristic, the sound pressure was mainly distributed in shaft frequency,blade frequency and frequency multiplication,the maximum sound pressure appeared at 1 time blade passing frequency. With the decrease of the flow rate,the SPL of the pump discharge was increased. Then,based on the bionics principle,the similarity criterion was used to establish the bionic blade model with reference to the structure characteristics of the specimen of the owl wings. Three parameters,including tooth width,tooth pitch and tooth width were constructed to control the geometry of the bionic blade,and these parameters were chosen to design 16 orthogonal test models. Finally,the internal flow and sound field datum of different impellers under different working conditions were got by calculation. Compared with the optimal model,the result showed that the bionic blade with sawtooth structures can reduce the pressure fluctuation,stabilize the flow field and reduce the noise. Noise reduction was obvious under the design condition,and the noise of the blade frequency was decreased ashigh as 8 d

关 键 词：管道泵 压力脉动 流动诱导噪声 仿生叶片 数值模拟 

分 类 号：TH311[机械工程—机械制造及自动化]