预报振动噪声的径向基点插值无网格与无限元耦合方法  

A meshless radial point interpolation coupled with improved infinite element method for predicting sound radiation

作　　者：吴绍维 向阳[2] 黄庭瑞 WU Shaowei;XIANG Yang;HUANG Tingrui(School of Shipping and Naval Architecture,Chongqing Jiaotong University,Chongqing 400074,China;School of Energy and Power Engineering,Wuhan University of Technology,Wuhan 400063,China;Anqing CSSC Diesel Engine Co.,Ltd.,Anqing 246005,China)

机构地区：[1]重庆交通大学航运与船舶工程学院,重庆400074 [2]武汉理工大学能源与动力工程学院,武汉400063 [3]安庆中船柴油机有限公司,安徽安庆246005

出　　处：《振动与冲击》2020年第10期32-43,共12页Journal of Vibration and Shock

基　　金：国家自然科学基金项目(51909016);重庆市教育委员会科学技术研究项目(KJQN201900705)。

摘　　要：为克服传统的有限元耦合无限元方法中的单元匹配问题,研究了径向基点插值法和无限元法的耦合规律,提出了一种预报无限域结构振动噪声的径向基点插值无网格与可变阶无限声波包络单元耦合方法,推导了预报声压的计算公式。为提高声场预报精度和满足声波在无限域的自由衰减,结构外部无限声场分为使用无网格表示的近场和可变阶声波包络单元离散的远场。在该耦合方法中,通过在近场与远场之间的交界面上配置虚拟网格来构造具有连续性的声压形函数,确保了声压的连续与一致性。采用数值仿真和试验对该耦合方法进行了验证,结果表明该耦合方法拥有无网格法的高精度和可变阶声波包络单元法满足声波自由衰减的特点,具有良好的精度和收敛性,可用于实际噪声预报。To eliminate the element matching in traditional method based on finite and infinite elements, the coupling of the radial point interpolation method(RPIM) and the variable order infinite acoustic wave envelope element(WEE)was studied. A RPIM coupled with improved WEE method was proposed for exterior sound problems in infinite domain. The coupling formula of this method was theoretically derived. To improve accuracy and properly imitate the amplitude decay of the outgoing travelling wave, the infinite acoustic field was divided into near and far acoustic fields, which were discretized by arbitrarily distributed nodes and WEEs respectively. The continuity and compatibility of the acoustic pressure were maintained by constructing hybrid acoustic pressure shape function on the fictitious meshin the near field along the interface between the two fields. Simulations and experiments were performed to test the method. The results show that the method can take full advantage of both the RPIM and WEE methods and is a valuable approach.

关 键 词：噪声 径向基点插值法(RPIM) 声波包络单元(WEE) 无限域 

分 类 号：O422.6[理学—声学] O429[理学—物理]