简要描叙FE法(finite element method)和WB法(wave based method)的理论背景以及耦合FE/WB法的数学基础.耦合FE/WB法利用两者的优势——FE法的广泛应用和WB法的高收敛特性,将FE模型中较大且几何简单的部分采用WB法代替.耦合模型具有相...简要描叙FE法(finite element method)和WB法(wave based method)的理论背景以及耦合FE/WB法的数学基础.耦合FE/WB法利用两者的优势——FE法的广泛应用和WB法的高收敛特性,将FE模型中较大且几何简单的部分采用WB法代替.耦合模型具有相对较少的自由度.对于较高的频率还可以进行细分得到更高的计算精度,并利用模态缩减法进一步减少自由度数.数值算例结果表明,该耦合方法有潜力覆盖中频段的声分析.展开更多
描叙了圆柱壳与声耦合系统建模技术的基本概念。根据WB法(Wave based method,简称WB法)的基本原理,将结构场变量和声压展开成波函数和特解函数的叠加。应用加权余量法将结构和声学边界条件以及结构与声耦合界面上的连续性条件转换成近...描叙了圆柱壳与声耦合系统建模技术的基本概念。根据WB法(Wave based method,简称WB法)的基本原理,将结构场变量和声压展开成波函数和特解函数的叠加。应用加权余量法将结构和声学边界条件以及结构与声耦合界面上的连续性条件转换成近似积分,推导出一组由代数方程表示的耦合模型。通过分析二维的算例表明这种预报技术计算量小且精度高,因此可应用到中频的分析。展开更多
This paper attempts to further extend the so-called Trefftz direct method(TDM), which has been developed and applied to a wide variety of boundary value problems in recent years. In this approach, the complete system ...This paper attempts to further extend the so-called Trefftz direct method(TDM), which has been developed and applied to a wide variety of boundary value problems in recent years. In this approach, the complete system of solutions of the partial differential equations is used as weighting functions and a non-singular boundary integral equation is used as the starting formulation. Several relative problems are discussed here. They are the problems of necessary and sufficient conditions for Trefftz-type boundary integral equations: the relationship between the Trefftz method and the variational principle and the infrequently encountered but possible singular problems in the Trefftz method and the treatment in practice. Numerical results are presented to illustrate the computational efficiency of the approach and to demonstrate its advantages.展开更多
文摘简要描叙FE法(finite element method)和WB法(wave based method)的理论背景以及耦合FE/WB法的数学基础.耦合FE/WB法利用两者的优势——FE法的广泛应用和WB法的高收敛特性,将FE模型中较大且几何简单的部分采用WB法代替.耦合模型具有相对较少的自由度.对于较高的频率还可以进行细分得到更高的计算精度,并利用模态缩减法进一步减少自由度数.数值算例结果表明,该耦合方法有潜力覆盖中频段的声分析.
文摘描叙了圆柱壳与声耦合系统建模技术的基本概念。根据WB法(Wave based method,简称WB法)的基本原理,将结构场变量和声压展开成波函数和特解函数的叠加。应用加权余量法将结构和声学边界条件以及结构与声耦合界面上的连续性条件转换成近似积分,推导出一组由代数方程表示的耦合模型。通过分析二维的算例表明这种预报技术计算量小且精度高,因此可应用到中频的分析。
基金Supported by National Natural Science Foundation of China(No.19872019).
文摘This paper attempts to further extend the so-called Trefftz direct method(TDM), which has been developed and applied to a wide variety of boundary value problems in recent years. In this approach, the complete system of solutions of the partial differential equations is used as weighting functions and a non-singular boundary integral equation is used as the starting formulation. Several relative problems are discussed here. They are the problems of necessary and sufficient conditions for Trefftz-type boundary integral equations: the relationship between the Trefftz method and the variational principle and the infrequently encountered but possible singular problems in the Trefftz method and the treatment in practice. Numerical results are presented to illustrate the computational efficiency of the approach and to demonstrate its advantages.
