A force-based quadrilateral plate element( 4NQP13) for the analysis of the plate bending problems using large increment method( LIM) was proposed. The LIM, a force-based finite element method( FEM),has been successful...A force-based quadrilateral plate element( 4NQP13) for the analysis of the plate bending problems using large increment method( LIM) was proposed. The LIM, a force-based finite element method( FEM),has been successfully developed for the analysis of truss,beam,frame,and 2D continua problems. In these analyses,LIMcan provide more precise stress results and less computational time consumption compared with displacement-based FEM. The plate element was based on the Mindlin-Reissner plate theory which took into account the transverse shear effects.Numerical examples were presented to study its performance including accuracy and convergence behavior,and the results were compared with the results have been obtained from the displacementbased quadrilateral plate elements and the analytical solutions. The4NQP13 element can analyze the moderately thick plates and the thin plates using LIMand is free from spurious zero energy modes and free from shear locking for thin plate analysis.展开更多
单元型光滑有限元方法(cell-based smoothed finite element method,CS-FEM)在计算系统总体刚度矩阵时,所得刚度矩阵改善了有限元方法"过硬"的数值缺陷。其结果与有限元相比:(1)利用CS-FEM模型,对于网格发生较大的形变时,无...单元型光滑有限元方法(cell-based smoothed finite element method,CS-FEM)在计算系统总体刚度矩阵时,所得刚度矩阵改善了有限元方法"过硬"的数值缺陷。其结果与有限元相比:(1)利用CS-FEM模型,对于网格发生较大的形变时,无需映射,可以得到更好的解析解;(2)CS-FEM是对光滑区域的边界利用散度定理积分,则无需对刚度矩阵中的形函数进行求导。展开更多
为了拓展图形学弹性体模拟中的各向异性超弹性虚拟材料种类,建立了基于虚拟纤维的本构模型.首先从能量可加性出发,将超弹性体应变能量密度函数分解为轴向、剪切、体积分量的纤维加和形式,然后建立单根纤维的轴向应变、剪切应变、体积应...为了拓展图形学弹性体模拟中的各向异性超弹性虚拟材料种类,建立了基于虚拟纤维的本构模型.首先从能量可加性出发,将超弹性体应变能量密度函数分解为轴向、剪切、体积分量的纤维加和形式,然后建立单根纤维的轴向应变、剪切应变、体积应变的应变度量,最后推导出各分量的应力表示.仿真实验使用基于四面体的非线性有限元法(finite element method,FEM),半隐式时间积分进行解算,并采用CPU串行算法,测试了不同场景下非线性能量函数以及纤维权重组合对虚拟纤维材料刚度、泊松效应、轴向特性的影响.结果表明,虚拟纤维本构模型具有大变形稳定性,材料参数设置可良好地展现上述物理特性,相比现有的横观各向同性模型具有更丰富的可调节能力.展开更多
基金National Natural Science Foundation of China(No.10872128)
文摘A force-based quadrilateral plate element( 4NQP13) for the analysis of the plate bending problems using large increment method( LIM) was proposed. The LIM, a force-based finite element method( FEM),has been successfully developed for the analysis of truss,beam,frame,and 2D continua problems. In these analyses,LIMcan provide more precise stress results and less computational time consumption compared with displacement-based FEM. The plate element was based on the Mindlin-Reissner plate theory which took into account the transverse shear effects.Numerical examples were presented to study its performance including accuracy and convergence behavior,and the results were compared with the results have been obtained from the displacementbased quadrilateral plate elements and the analytical solutions. The4NQP13 element can analyze the moderately thick plates and the thin plates using LIMand is free from spurious zero energy modes and free from shear locking for thin plate analysis.
文摘单元型光滑有限元方法(cell-based smoothed finite element method,CS-FEM)在计算系统总体刚度矩阵时,所得刚度矩阵改善了有限元方法"过硬"的数值缺陷。其结果与有限元相比:(1)利用CS-FEM模型,对于网格发生较大的形变时,无需映射,可以得到更好的解析解;(2)CS-FEM是对光滑区域的边界利用散度定理积分,则无需对刚度矩阵中的形函数进行求导。
文摘为了拓展图形学弹性体模拟中的各向异性超弹性虚拟材料种类,建立了基于虚拟纤维的本构模型.首先从能量可加性出发,将超弹性体应变能量密度函数分解为轴向、剪切、体积分量的纤维加和形式,然后建立单根纤维的轴向应变、剪切应变、体积应变的应变度量,最后推导出各分量的应力表示.仿真实验使用基于四面体的非线性有限元法(finite element method,FEM),半隐式时间积分进行解算,并采用CPU串行算法,测试了不同场景下非线性能量函数以及纤维权重组合对虚拟纤维材料刚度、泊松效应、轴向特性的影响.结果表明,虚拟纤维本构模型具有大变形稳定性,材料参数设置可良好地展现上述物理特性,相比现有的横观各向同性模型具有更丰富的可调节能力.