郭立伟, 刘晓宇, 李世海. 波动数值模拟中的吸收边界条件[J]. 工程力学, 2011, 28(9): 17-022,.
引用本文: 郭立伟, 刘晓宇, 李世海. 波动数值模拟中的吸收边界条件[J]. 工程力学, 2011, 28(9): 17-022,.
GUO Li-wei, LIU Xiao-yu, LI Shi-hai. ABSORBING BOUNDARY CONDITION IN NUMERICAL SIMULATION OF WAVE PROPAGATION PROBLEMS[J]. Engineering Mechanics, 2011, 28(9): 17-022,.
Citation: GUO Li-wei, LIU Xiao-yu, LI Shi-hai. ABSORBING BOUNDARY CONDITION IN NUMERICAL SIMULATION OF WAVE PROPAGATION PROBLEMS[J]. Engineering Mechanics, 2011, 28(9): 17-022,.

波动数值模拟中的吸收边界条件

ABSORBING BOUNDARY CONDITION IN NUMERICAL SIMULATION OF WAVE PROPAGATION PROBLEMS

  • 摘要: 为了提高人工边界条件在波动输入边界和自由场边界的精度,该文扩展了Higdon一阶吸收边界条件,并编制了相应的有限元计算程序。该方法将输入波分量引入到Higdon吸收边界条件当中,利用最小二乘法,用吸收边界邻域内的应变场和速度场计算Higdon边界条件公式中的参数,实现了吸收边界条件的自动更新。并且,该文提出了既适用于波动输入边界又适用于自由场边界的速度边界和力边界两种吸收边界条件。算例表明,与传统人工边界条件相比,该文建议的吸收边界条件具有良好的模拟效果。

     

    Abstract: The first-order absorbing boundary condition is extended to improve accuracy both on the free field boundary and the input wave boundary. The computer program of this absorbing boundary condition is based on finite element method. The input wave is introduced into Higdon’s boundary condition by using least-squares method, while the parameters in Higdon’s operator are estimated by the nodal strain and velocity fields inside absorbing boundary. As a result, the absorbing boundary condition is updated automatically. The velocity boundary condition and the force boundary condition are proposed to absorb reflected wave both on the free field boundary and the input wave boundary. Numerical examples show that the proposed boundary conditions have much higher accuracy compared with the conventional artificial boundary conditions.

     

/

返回文章
返回