Multicloud Convergence Acceleration for Complex Applications on Arbitrary Grids

A method is presented which dramatically enhances convergence of discrete systems for a wide variety of discretizations, including finite difference, finite volume, and mixed element approaches. The method, termed ldquomulticloud,rdquo was first introduced in a previous work by Katz and Jameson.[5] This work concerns two major enhancements to multicloud: 1) The integration of multicloud procedures for arbitrary and mixed meshes, and 2) the development of automatic coarsening procedures to obtain coarse levels for the multicloud procedure. The first enhancement involves the use of meshless scheme to damp out unresolvable high frequency modes present on a conventional mesh. Because the meshless scheme is only used on coarse levels, the final solution retains any and all conservative properties of the parent mesh. The second enhancement allows for the automatic creation of coarse point distributions given a conventional mesh. Thus, the multicloud procedure may be used with no extra mesh generation tools needed. These two enhancements create a powerful convergence acceleration technique which is entirely mesh transparent, lending itself well to complex configurations in which mixed grid types are used and for which efficiency is of the utmost importance.