Tetrahedral versus hexahedral finite elements in numerical modelling of the proximal femur
Tetrahedral versus hexahedral finite elements in numerical modelling of the proximal femur
复制标题
DOI：
10.1016/j.medengphy.2005.12.006
复制
发表时间：
2006-11-01
影响因子：
2.2
通讯作者：
Simoes, J. A.
中科院分区：
文献类型：
--
作者：
Ramos, A.;Simoes, J. A.
本研究的目的是评价和比较简化和真实近端完整股骨几何形状的四面体和六面体有限元网格。推导了股骨简化模型的应力和应变的理论表达式。为了分析近端股骨的真实几何形状，使用第三代复合股骨的CAD模型（Pacific Research Labs，Vashion Island，WA），并使用Hyperworks（Altair Engineering，Inc.，Troy，MI）有限元分析软件。收敛测试与六面体（8-和20-节点砖元素）和四面体（4-和10-节点四面体）元素进行了分析，通过比较骨膜冯米塞斯应力和主应变在选定的点的股骨。数值骨膜应变也与实验进行了比较，以确定有限元的准确性。总的来说，我们得出结论，对于简化的股骨，四面体线性元素允许的结果更接近理论的，但六面体二次元素似乎更稳定，影响程度的细化（NDOF）的网格。无法将这些结果与实际股骨近端模拟中观察到的结果相关联，其中使用精细网格未观察到显著差异，六面体单元的NDOF=20000以上。(c)2005年IPEM。由爱思唯尔有限公司出版。保留所有权利。
The objective of this study was to evaluate and compare tetrahedral and hexahedral finite element meshes of simplified and realistic proximal intact femur geometries. Theoretical expressions of stresses and strains were derived for the simplified model of the femur. For the analysis of the realistic geometry of the proximal femur, a CAD model of the third generation composite femur (Pacific Research Labs, Vashion Island, WA) was used and simulations were performed with Hyperworks (R) (Altair Engineering, Inc., Troy, MI) finite element analysis software. Convergence tests with hexahedral (8- and 20-node brick-elements) and tetrahedral (4- and 10-node tetrahedrons) elements were analysed by comparing the periosteal von Mises stresses and principal strains at a selected point of the femur. The numerical periosteal strains were also compared with experimental ones to determine the accuracy of the finite elements. Overall, we concluded, for the simplified femur, that tetrahedral linear element allowed results more closely to theoretical ones, but hexahedral quadratic elements seem to be more stable and less influenced to the degree of refinement (NDOF) of the mesh. It was not possible to correlate these findings with those observed for the realistic proximal femur simulations where no significant differences were seen using refined meshes, with more than NDOF=20000 for hexahedral elements. (c) 2005 IPEM. Published by Elsevier Ltd. All rights reserved.