无限长FFS圆柱壳体远场辐射声压的参数研究  

Parametric study on far-field sound pressure radiation from an infinite FFS cylindrical shell

作　　者：李洪亮[1] 吴成军[1] 黄协清[1] 

机构地区：[1]西安交通大学振动与噪声控制工程研究所,西安710049

出　　处：《农业工程学报》2003年第3期41-45,共5页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金资助项目 (50 0 0 50 1 5)

摘　　要：该文以无限长 F FS( Fluid F illed/Subm erged)圆柱壳体的远场声压谱为研究对象 ,利用波数域法建立了在集中载荷作用下 ,无限长 F FS圆柱壳体的径向波数域振动速度计算公式 ,进而利用边界积分方程求得了该类壳体的远场辐射声压表达式。这里的流体为一维轴向、无旋、无粘的匀质流体。并利用这个理论模型 ,研究了流体类型 (轻质、重质 ) ,流体速度 ,壳体阻尼 ,力的作用方向 (径向、切向、轴向 )等参数变化对无限长 FF S圆柱壳体声辐射的影响规律 ,旨在为工程中大量存在的输流管道减振降噪优化设计提供指导原则。数值模拟结果表明 :对于声波逆流传播 ,随着流速增加 ,远场辐射声压增加 ;对于空气这种轻质流体 ,其流动对壳体远场辐射声压影响较小。而增加圆柱壳体的结构阻尼 ,可以有效降低其远场辐射声压。该文的研究结果对农机和加工设备的低噪声优化设计有一定的参考价值。The far field sound radiation spectra of an infinite FFS(fluid filled/submerged) cylindrical shell was studied when a simply harmonic point force applied on it. The formulae of the radial velocity of an infinite FFS cylindrical shell under the concentrated excitation in wave number domain were developed by using wave number domain approach (WDA). Then, the analytical expressions were derived for the far field sound pressure radiating from the cylindrical shell by using Boundary Integral Equation(BIE). Here, the fluid is non viscous, isotropic and irrotational coaxial flow. Based on it, the influences of parameters such as kinds of fluid, structural damping, direction of the force on the far field pressure were also investigated. It was shown that the pressure and the resonance frequency would increase with the fluid velocity increasing for downstream propagation. Furthermore, the motion of the light fluid, such as air, has little effect on the far field sound radiation spectrum. Increasing the structural damping is a useful method to control the sound radiation. This paper gives some guidelines on the optimized design of the agricultural mechanism for noise reduction.

关 键 词：无限长FFS圆柱壳体 波数域 边界积分方程 远场声压 流速 低噪声优化设计 

分 类 号：O328[理学—一般力学与力学基础]