三维体单元多级细化方法研究

传统方法采用六面体单元进行局部细化,模型准备时间长,对于复杂边界处容易造成单元畸变,甚至需要四面体单元过渡,大大降低了求解精度.在h法和原有单元过渡法的基础上,提出了体单元多级细化方法,并给出了实现形式,然后通过与Hertz法和常规细化法的对比,验证了该方法的有效性.最后,针对多级细化带来的边界过刚度问题,采用扩大细化区的方法予以解决,并以轧机辊系接触问题为例进行了分析验证.

Study on Multilevel Refinement of 3-D Elements

Conventionally the local refinement of mesh division is done via the hexahedral elements, which takes a long time to develop relevant mathematical model and distorts the elements at complex boundaries even requires the tetrahedral transition, thus lowering the solution accuracy. For this reason, the multilevel refinement method (MRM) of elements is proposed with the way given to implement it, based on the h-method and existing element transition. The effectiveness of MRM is verified by comparing it with Hertz method and other conventional refinement method. As to the problem of local excessive stiffness at boundaries as a result of multilevel refinement, the solution is to expand the refinement area, which has been verified by an exemplification of the rolls in contact on a mill.