非结构多面体二阶局部保界全局重映算法

Second-order Local-Bound-Preserving Conservative Remapping on Unstructured Polyhedral Meshes

提出一种三维非结构多面体二阶保界全局重映算法.在旧网格上选取模板利用最小二乘构造插值多项式,采用凸包算法计算多面体相交部分,最后使用局部保界修正技术修补重映后的越界量.多项数值实验表明这种格式同时具有高精度、高分辨率和高效率的特点.

We present conservatively remapping cell-centered variables from one mesh to another with second-order accuracy and boundary-preservation.It is generally applicable to any polyhedral source or target mesh.The algorithm consists of four parts：A least square based polynomial reconstruction of physical gradient;an octree-based fast donor-cell searing algorithm;a convex hull algorithm for intersection of polyhedrons and a modifying procedure for local bound preservation.The remapping scheme is scalable,second-order accurate and enjoys bound preservation property.Various benchmark problems demonstrate these properties.Numerical results show that it takes hundreds seconds to remap physical variables on tessellation with hundreds thousands to millions polyhedrons.