计算力学学报2012，Vol.29Issue(3)：368-374,7.
离散颗粒集合体-Cosserat连续体模型的连接尺度方法
Bridging scale method for discrete particle assembly-Cosserat continuum modeling
摘要
Abstract
On the basis of the bridging scale method （BSM） initially proposed for molecular dynamics- Cauchy continuum modeling , a new version of the BSM that couples the discrete particle assembly model using the discrete element method （DEM） and the Cosserat continuum model using the finite ele- ment method （FEM） in fine and coarse scales respectively is presented. The present BSM applies the DEM only to limited local regions of the whole computational domain for the purpose of accurate simula- tion of material failure with discontinuous deformation characteristics in microscopic scale,and meantime applies the FEM that costs much less both computational time and storage space to the whole domain. In addition,different time step sizes are allowed to the time integration schemes used to the coarse and fine scales respectively,as a consequence, both computational accuracy and efficiency of the present BSM is greatly enhanced. With the coarse and fine scale decomposition of translational and rotational displace- ments,in light of the principle of virtual work applied to the FEM nodes of Cosserat continuum and the particle centers of discrete particle assembly respectively, two decoupling sets of equations of motion of the combined coarse-fine scale system are derived. The interfacial condition between coarse and fine do- mains in the case of quasi-static loading,and the non-reflecting boundary condition （NRBC）, which is ca- pable of effectively eliminating spurious reflective waves at the interface between coarse and fine domains under dynamic loads are presented and discussed. The numerical results for 2D example problems illus- trate the applicability and advantages of the present BSM,as well as the availability of the proposed in- terfacial condition for dynamical response simulations of granular materials.关键词
颗粒材料/连接尺度方法/离散单元法/Cosserat连续体/多尺度/非反射边界条件Key words
granular material/bridging scale method/discrete element method/cosserat continuum/multi-scale/non-reflecting boundary condition分类
数理科学引用本文复制引用
万柯,李锡夔..离散颗粒集合体-Cosserat连续体模型的连接尺度方法[J].计算力学学报,2012,29(3):368-374,7.基金项目
国家自然科学基金(90715011,11072046,10672033) （90715011,11072046,10672033）
国家重点基础研究发展计划(973)(2010CB731502)资助项目 （973）
