局部精细化网格会导致结构有限元动力学分析的计算时间大幅增加.为了提高计算效率，结合域分解法与子循环方法，提出一种基于多重节点的结构动力学显式异步长并行计算方法.该方法采用节点分割将模型划分为若干子分区，子分区采用显式Newmark时间积分格式并根据分区单元特性选用时间步长；相邻分区通过多重节点构成耦合区域，小步长分区子循环过程中不涉及边界数据的插值过程.“天河二号”超算平台上的算列表明：采用显式异步长并行方法计算结构动力学问题，在提高计算效率的同时可以保持较高的计算精度.
The local refined mesh leads to a large increase of calculation time in the structural dynamic finite element analysis. In order to improve the calculation efficiency, an explicit asynchronous parallel computational method based on multiple overlapping nodes is proposed. The procedure combines domain decomposition with subcycling method. The whole structure is divided into several subdomains by node partition method and the integral step size is selected according to the internal mesh sizes of the subdomain. An explicit Newmark time integral scheme is adopted in the subdomain. Multiple overlapping nodes between different subdomains constitute the coupling region without the interpolation process in the subcycling process. Simulation results of two cases implemented on Tianhe 2 supercomputer platform show that the proposed method can improve the computational efficiency with a high computational accuracy.
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