本帖最后由 yanyu7long 于 2019-11-14 19:35 编辑
黏性系数实际上是为了解决cohesive单元失效过程引起的数值不稳定或回弹(snap back),而人为引入的黏性耗散,实际上改变了cohesive界面本构(加强), 而实际影响了局部精度。但我们关注的往往是全局的精度,而不太在意裂尖的细节。黏性系数越小越好也是自然的,既要保证收敛,又要减小人为引入其带来的误差。
引进黏性系数总体而言是在原有断裂能的基础上增加了断裂过程中的黏性耗散,二者共同消耗周围弹性体释放的弹性应变能。具体效果而言是延缓了损伤,增大了分离强度。
参考文献:
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Prof. Gao Y.F. 的详细代码可在其主页下载:
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