计算物理 ›› 2014, Vol. 31 ›› Issue (5): 514-522.

• 论文 • 上一篇    下一篇

一种适合基于原子尺度有限元方程的低通滤波边界条件

任国武, 汤铁钢, 李庆忠   

  1. 中国工程物理研究院流体物理研究所, 四川 绵阳 621999
  • 收稿日期:2013-09-12 修回日期:2013-12-19 出版日期:2014-09-25 发布日期:2014-09-25
  • 作者简介:任国武(1981-),男,助理研究员,主要从事材料力学计算研究,E-mail:guowu.ren@gmail.com
  • 基金资助:
    国家自然科学基金(11102191);流体物理研究所发展基金(SFZ20120402)资助项目

Low-pass Filter Boundary Condition for Atomic-based Finite Element Method

REN Guowu, TANG Tiegang, LI Qingzhong   

  1. Institute of Fluid Physics, China Academy qf Engineering Physics, Mianyang, Sichuttn 621999, China
  • Received:2013-09-12 Revised:2013-12-19 Online:2014-09-25 Published:2014-09-25

摘要: 发展一种基于原子尺度的有限元动力学方程,其动态行为跨越了从原子尺度到宏观尺度.理论计算该方程的色散关系和动力学散射特征.在此基础上,基于滤波器的概念,设计低通滤波边界条件用于减少网格增大带来的高频反射波,同时又保证低频振动波传播不受影响.通过一维数值模拟,计算了能量反射和透射系数,展示低通滤波边界条件可以吸收高频反射波而不影响低频波的传播.

关键词: 有限元, 滤波, 反射系数

Abstract: An atomic-based finite element method is developed,spanning from atomic scale to macroscopic one. With theoretical deduction dispersion relation and dynamic scattering behavior are calculated. For spurious reflection caused by non-uniform grid,lowpass filter boundary condition is designed to effectively eliminate the reflection of high-frequency phonons,while keeping low-frequency ones transparent. These schemes are demonstrated with numerically calculating reflection and transmission coefficients in onedimensional modeling.

Key words: finite element, filter, reflection coefficient

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