摘要
针对浸没在无限水域中的水下结构声固耦合问题,基于有限元(FEM)与比例边界有限元法(SBFEM)建立了水下结构声固强耦合公式。在该耦合公式中,水下结构用FEM模拟,而无限水域截断成有限水域与剩余的无限水域,其中有限水域用声学FEM模拟,剩余的无限水域用SBFEM模拟。水下结构与有限水域的耦合效应及有限水域与无限水域的耦合效应通过耦合面的运动学条件及动力学条件获得。基于耦合面的运动学及动力学条件,建立水下结构与周边无限水域的FEM-SBFEM强耦合公式。利用该耦合公式,采用Newmark直接积分法分析了水下结构的瞬态响应。数值分析结果表明了该FEM-SBFEM耦合公式的正确性。相比于FEM模拟无限水域,该耦合公式具有自由度少、精确满足无限水域无反射等特点,可为水下结构动力响应分析提供一种新的分析手段。
For acoustic- structure coupling problems of submerged structures in infinite fluid,this study proposed a strong coupling formulation of submerged structures based on FEM and scaled boundary finite element method（ SBFEM）. In the formulation,FEM was used to model submerged structures,while infinite fluid was truncated into bounded fluid and the remaining infinite fluid. The bounded fluid was modeled by FEM,while the remaining infinite fluid was modeled by SBFEM. Coupling effects between submerged structures and bounded fluid,and between bounded fluid and the remaining infinite fluid,were obtained through kinematics and dynamics conditions along coupling surfaces. Based on these kinematics and dynamics conditions of coupling surfaces,a FEM- SBFEM strong coupling formulation was built for submerged structures and surrounding infinite fluid. Based on the coupling formulation,use the Newmark direct integral method to analyze transient responses of submerged structures. Numerical results show the FEM- SBFEM formulation＇s correctness. Comparing to FEM modeling infinite fluid,the formulation has some advantages such as small degree of freedom＇s number and exactly satisfying infinite fluid＇s radiation conditions,which provided a new analysis manner for submerged structure dynamic responses.
出处
《西南科技大学学报》
CAS
2015年第4期73-77,共5页
Journal of Southwest University of Science and Technology
基金
国家自然科学基金项目(10902060)
中国工程物理研究院科学技术发展基金(2011B0201036)
