圆柱及切割圆柱低Mach数绕流气动声辐射  

Aerodynamic sound radiation of low Mach number flows around a cylinder and truncated cylinders

作　　者：蔡建程[1,2] 余梦瑶 陈超倩 夏文俊 鄂世举[1,2] CAI Jiancheng;YU Mengyao;CHEN Chaoqian;XIA Wenjun;E Shiju(College of Engineering,Zhejiang Normal University,Jinhua 321004;Key Laboratory of Urban Rail Transit Intelligent Operation and Maintenance Technology&Equipment of Zhejiang Province,Jinhua 321005)

机构地区：[1]浙江师范大学工学院,金华321004 [2]浙江省城市轨道交通智能运维技术与装备重点实验室,金华321005

出　　处：《声学学报》2023年第5期978-988,共11页Acta Acustica

基　　金：国家自然科学基金项目(51976201);浙江省自然科学基金项目(LY22E060006)资助。

摘　　要：以柱体绕流声辐射为研究对象,探讨低Mach数流动气动声定量预测方法。首先,理论分析Lighthill声类比理论与基于流体动力学压力对时间求导的扰动分离模型之间内在联系。其次,利用计算流体动力学对圆柱及其尾部切割后的亚临界流态绕流进行二维数值求解,分析两种湍流模型的流场计算效果。最后,分别使用声类比理论FW-H方程及扰动分离模型进行柱体绕流气动声辐射定量预测,分析声指向性及频谱特性。数值结果表明声类比理论与扰动分离模型预测的声辐射频谱相似,但前者的幅值略高;圆柱尾部切割使尾流脉动增强,导致声辐射变大。Taking the sound radiation of flow past cylinders as the research objective,the quantitative prediction methods of aerodynamic sound in low Mach number flows are discussed.Firstly,the intrinsic relationship between the Lighthill’s acoustic analogy and an acoustic perturbation equation based on the acoustic/viscous splitting technique,is analyzed.Secondly,based on computational fluid dynamics,the two-dimensional(2D)simulations of the subcritical flow around a cylinder and two truncated cylinders are carried out,and performances of the two turbulence models are discussed.Finally,the aerodynamic sound radiations are predicted using the FW-H equation in the Lighthill’s acoustic analogy theory as well as the non-homogeneous wave equation of the acoustic perturbation theory,and the acoustic directivity and spectral characteristics are analyzed.The numerical results show that the acoustic radiations predicted by the FW-H equation and the acoustic perturbation equation are similar in the acoustic spectra with the larger amplitude by the FW-H equation.The truncation of the cylinder at the rear part makes the wake flow fluctuations increase resulting in more intensive sound radiation.

关 键 词：声类比 声扰动方程 低Mach数流动 柱体绕流 

分 类 号：O357.5[理学—流体力学] O42[理学—力学]