并行化非结构重叠网格隐式装配技术

重叠网格技术广泛应用于复杂外形及多体分离问题的数值模拟，但是超大规模重叠网格装配的鲁棒性和效率依然是实际应用中的瓶颈。基于格心型的有限体积格式，发展了一种并行化的非结构重叠网格隐式装配技术。该技术采用节点的壁面距离作为插值边界的判断准则，并通过物理边界推进确定出活跃区域。此外，基于网格分区策略实现了隐式装配技术的并行化，为了能够适应超大规模的计算网格，在每一个网格子区内单独建立用于查询的交替数字树（ADT）数据结构，整体网格点在各个子区内进行查询，并通过信息通讯接口（MPI）传递查询结果并进行逻辑判断。该并行化的非结构重叠网格隐式装配技术具有较高的自动化程度，通过多体装配算例以及机翼外挂物分离算例，证明了该方法的实用性。

Parallel implicit hole-cutting method for unstructured overset grid

The overset grid is widely used for numerical simulation of the complex configuration and multi-bodies separation problems. However, the practicability and robustness of hole-cutting for the large scale grid is still a bottleneck problem. In this paper, a parallel implicit hole-cutting method for the unstructured overset grid is developed. The boundary between the active and the negative regions is determined by wall distance and donor cell searching. The front advancing method is adopted to identify the active region. The parallel strategy is implemented based on the partitioned grids. To reduce the memory consumption of the large scale grid, Alternating Digital Tree (ADT) is built merely on each sub-zone. Global nodes are searched in the sub-zones of the present processor, and their status is finally determined through Message Passing Interface (MPI) communication. This parallel method is highly automatic and can be used for the large scale grid. The practicability and robustness of the method proposed is verified by several hole-cutting and the wing/store configuration separation test cases.