基于比例边界有限元法和有限元法的水下结构瞬态分析方法  

TRANSIENT ANALYSIS METHOD OF SUBMERGED STRUCTURE BASED ON SBFEM AND FEM

作　　者：李上明[1] 

机构地区：[1]中国工程物理研究院总体工程研究所,四川绵阳621900

出　　处：《工程力学》2013年第11期42-46,共5页Engineering Mechanics

基　　金：国家自然科学基金项目(10902060;11272299);中国博士后科学基金特别项目(201003123);中国工程物理研究院科学技术发展基金项目(2011B0201036)

摘　　要：针对冲击波作用下水下结构与无限声学水域的流固耦合问题,建立了基于比例边界有限元法和有限元法的瞬态分析方法。无限水域用比例边界有限元法离散,而水下结构等有限域用有限元法模拟。该方法利用声学近似法将无限水域施加给水下结构的载荷分解成冲击波载荷和散射波载荷。冲击波载荷由水下冲击波理论确定,而散射波载荷由比例边界有限元法估值。为改善比例边界有限元法动态质量矩阵的计算效率,发展了动态质量矩阵的时域递推公式。数值算例分析结果表明了所发展的瞬态分析方法和时域递推公式的正确性。Aiming at fluid-structure interaction problems between a submerged structure subjected to shock waves and infinite acoustic fluid, a transient analysis method is proposed based on the scaled boundary finite element method （SBFEM） and finite element method （FEM）. The infinite fluid is discretized by the SBFEM and the bounded domain such as the submerged structure is modeled by the FEM. Using the acoustic approximation method, the proposed method decomposes the loadings on the submerged structure applied by infinite fluid into shock wave loadings and scattered wave loadings. Shock wave loadings is determined by the underwater shock wave theory, while scattered wave loadings is evaluated by the SBFEM. A time-domain recursive formulation is proposed to improve the SBFEM dynamic mass matrix calculation efflcency. Numerical examples results show the accuracy of the proposed analysis method and the time-domain recursive formulation.

关 键 词：比例边界有限元法 无限水域 水下结构 瞬态分析 水下冲击 流固耦合 

分 类 号：TV36[水利工程—水工结构工程]