Study on reverse-quadtree adaptive grid technique

The fast multipole method is universally adopted for solving the convection equation in the vortex method. In this paper, a reverse-quadtree adaptive grid technique is proposed in order to improve the quadtree adaptive grid technique in the fast multipole method. Taking flow past a cylinder as an example, the results indicate the reverse-quadtree scheme can save more calculation time than the quadtree scheme when the particle population is large enough.