现场虚拟消声室构建与装备降噪方法研究

项目名称： 现场虚拟消声室构建与装备降噪方法研究

项目编号： No.51275469

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 机械、仪表工业

项目作者： 卢奂采

作者单位： 浙江工业大学

项目金额： 80万元

中文摘要： 针对重大装备因物理尺寸太大或结构太复杂等原因无法利用现有的消声室进行噪声测量评估的共性难题，提出在装备制造现场构建非物理的虚拟消声室的新思路，为在实际环境噪声中精确测量评估装备辐射的噪声提供虚拟自由声场的新方法。基于声波传播具有空间指向性的物理特性和近场声全息理论，重构非自由声场及建立分解装备噪声和环境噪声的计算模型，研究非自由声场参数求解方法，探索基于传声器阵列方法的非物理虚拟自由声场构建理论和虚拟消声室构建方法。理论分析非自由声场数学模型的正交基函数特性、声场参数正则化和优化计算方法，实验研究传声器阵列的安装位置、几何尺寸、形状、节点分布和传声器数量等参数的变化对虚拟自由声场精度的作用规律，建立虚拟消声室原型系统，研发具有自主知识产权的计算软件。本项目研究成果将对重大装备进行精确的现场声学测量评估和减振降噪具有重要理论意义和工程应用价值。

中文关键词： 现场虚拟消声室；声波分离方法；近场声全息；背景噪声抑制；虚拟自由声场

英文摘要： A new methodology of reconstructing non-free sound field and virtual anechic chamber in-situ and open air is proposed, in order to eliminate the environmental noise and the need of sound enclusure or anechoic chamber, for obtaining accurate sound measurements of oversized and/or complex structures which can not be tested inside exsisting anechoic chamber. The mathematical model of reconstruction of non-free sound field is developed based on the superposition of finite basis functions，which describe the direction and wavenember of sound waves in space, the algorithem to solve the coefficients of those basis functions is derived using nearfiled acoustic holography. The selection of orthogonal basis functions, the regularization of trasfer matrises mainly based on Truncated and Weighted Singular Value Decomposition，TWSVD, combined with Ordinary Cross Validation, OCV, and Generalized Cross Validation, GCV, as well as optimizationn of regularization parameters are throughly studied via numerical sumulations and experiments. The effectiveness of change of the parameters of microphone array, such as stand-off distance, size, geometry, coordinations of measurement point, and number of microphones, affect the acuracy of reconstruction of non-free field at steady state is intensively investigated. A prototype of virtual a

英文关键词： In-situ Virtual Anechoic；Sound Wave Separation Method；Near-field Acoustic Holography；Suppression of Background Noise；Virtual Free field