• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Solution of linear elastostatic and elastodynamic plane problems by the meshless local Petrov-Galerkin method.
【24h】

Solution of linear elastostatic and elastodynamic plane problems by the meshless local Petrov-Galerkin method.

机译：用无网格局部Petrov-Galerkin方法求解线性弹性静力和弹性动力平面问题。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The meshless local Petrov-Galerkin (MLPG) method is used to numerically find an approximate solution of plane strain/stress linear elastostatic and elastodynamic problems. The MLPG method requires only a set of nodes both for the interpolation of the solution variables and the evaluation of various integrals appearing in the problem formulation. The monomial basis functions in the MLPG formulation have been enriched with those for the linear elastic fracture mechanics solutions near a crack tip. Also, the diffraction and the visibility criteria have been added to make the displacement field discontinuous across a crack. A computer code has been developed in Fortran and validated by comparing computed solutions of three static and one dynamic problem with their analytical solutions. The capabilities of the code have been extended to analyze contact problems in which a displacement component and the complementary traction component are prescribed at the same point of the boundary.; The code has been used to analyze stress and deformation fields near a crack tip and to find the stress intensity factors by using contour integrals, the equivalent domain integrals and the J-integral and from the intercepts with the ordinate of the plots, on a logarithmic scale, of the stress components versus the distance ahead of the crack tip. We have also computed time histories of the stress intensity factors at the tips of a central crack in a rectangular plate with plate edges parallel to the crack loaded in tension. These are found to compare favorably with those available in the literature. The code has been used to compute time histories of the stress intensity factors in a double edge-notched plate with the smooth edge between the notches loaded in compression. It is found that the deformation fields near the notch tip are mode-II dominant. The mode mixity parameter can be changed in an orthotropic plate by adjusting the ratio of the Young's moduli in the axial and the transverse direction.; The plane strain problem of compressing a linear elastic material confined in a rectangular cavity with rough horizontal walls and a smooth vertical wall has been studied with the developed code. Computed displacements and stresses are found to agree well with the analytical solution of the problem obtained by the Laplace transform technique.; The Appendix describes the analysis with the finite element code ABAQUS of the dependence of the energy release rate upon the crack length in a polymeric disk enclosed in a steel ring and having a star shaped hole at its center. A starter crack is assumed to exist in one of the leaflets of the hole. The disk is loaded either by a pressure acting on the surfaces of the hole and the crack or by a temperature rise. Computed values of the energy release rate obtained by modeling the disk material as Hookean are found to be about 30% higher than those obtained when the disk material is modeled as Mooney-Rivlin. The latter set of results accounts for both material and geometric nonlinearities.
机译：使用无网格局部Petrov-Galerkin（MLPG）方法在数值上找到平面应变/应力线性弹性静力学和弹性力学问题的近似解。 MLPG方法仅需要一组节点即可用于求解变量的插值和对问题表述中出现的各种积分的评估。 MLPG公式中的单项基本函数已经丰富了裂纹尖端附近的线性弹性断裂力学解决方案的函数。另外，增加了衍射和可见度标准，以使位移场在整个裂纹处不连续。已在Fortran中开发了一种计算机代码，并通过将三个静态和一个动态问题的计算解与它们的解析解进行比较来进行验证。该代码的功能已扩展为分析接触问题，其中在边界的同一点规定了位移分量和互补牵引力分量。该代码已用于分析裂纹尖端附近的应力和变形场，并通过使用轮廓积分，等效域积分和 J 积分以及纵坐标的截距来查找应力强度因子。应力分量与裂纹尖端前方距离的对数图的对数比例。我们还计算了矩形板中心裂纹尖端处的应力强度因子的时间历史，该矩形板的板边缘平行于受力加载的裂纹。发现它们与文献中的那些相比具有优势。该代码已用于计算双边缺口板中应力强度因子的时间历史记录，缺口之间的平滑边在压缩中加载。发现切口尖端附近的变形场是II型主导。通过在轴向和横向上调整杨氏模量的比值，可以在正交各向异性板中改变模式混合参数。用已开发的代码研究了压缩线性弹性材料的平面应变问题，该线性弹性材料被压缩在具有粗糙水平壁和光滑垂直壁的矩形腔中。发现计算的位移和应力与通过拉普拉斯变换技术获得的问题的解析解非常吻合。附录描述了使用有限元代码ABAQUS进行的分析，该分析取决于能量释放速率对封闭在钢环中并在中心具有星形孔的聚合物圆盘中裂纹长度的依赖性。假定在孔的一个小叶中存在一个起始裂纹。通过作用在孔和裂纹表面上的压力或温度升高来加载磁盘。发现通过将磁盘材料建模为Hookean而获得的能量释放率的计算值比将磁盘材料建模为Mooney-Rivlin时所获得的能量释放率大约高30％。后一组结果说明了材料和几何非线性。

著录项

  • 作者

    Ching, Hsu-Kuang.;

  • 作者单位

    Virginia Polytechnic Institute and State University.;

  • 授予单位 Virginia Polytechnic Institute and State University.;
  • 学科 Applied Mechanics.; Engineering Mechanical.
  • 学位 Ph.D.
  • 年度 2002
  • 页码 213 p.
  • 总页数 213
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 应用力学;机械、仪表工业;
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号