结构碰撞数值模拟的一类接触算法

本文提出了用于结构碰撞数值模拟的接触算法,包括接触搜索算法和接触力算法。在全局搜索过程中,引入了立方格和链表技术,使搜索的运算量由现有的O(Nlog₂N)降低为O(N)。在局部搜索过程中使用了自由曲面造型技术,提高了搜索精度,消除了“死区”现象。为便于与现有有限元软件连接,将全局搜索与局部搜索合并进行。本文给出的接触力算法既与显式时间积分格式相容,又能充分满足接触约束条件。文中给出了数值算例。

A NEW CONTACT ALGORITHM FOR NUMERICAL SIMULATION OF STRUCTURE CRASHWORTHINESS

A new algorithm for contact searching and computation of contact forces in crashworthiness analysis of structures is presented. The concepts of cell and linked-list are introduced to perform the global contact searching. The total cost of the search is reduced from O(Nlog2N) to O(N). Because the free-surface patch is used to model the contact surface, the accuracy of local contact searching increases and the dead-zone problem is resolved. In this new algorithm, the global and local searching processes are combined into one for the utilization in finite-element code. The contact force algorithm proposed in this paper is compatible with the explicit integration scheme, and the contact constraint conditions are well satisfied. Numerical results are given to demonstrate the performance of the new algorithm.