Regridding

Most chombo-discharge simulations will benefit from using AMR where grids change in time. When new grids are generated, the following situations occur:

1. Grids were removed, and data underneath the old grids must be replaced by coarsened data from the fine grids.

2. Grids were added, and data on those grids must be interpolated from the coarse data underneath them.

When grids are removed/added, computational particles must be also be associated with the new grids.

Coarsening data

When removing grids, we simply keep the old grid data. We thus assume that, prior to regridd, the user coarsened the data appropriately, see Coarsening data.

Interpolation

chombo-discharge currently supports interpolation onto the new grids using:

1. Constant interpolation, where the fine-grid data is initialized using the value in the coarse grid cells.

2. With minmod slope-limiters.

The API for interpolating onto the new grids is given in AmrMesh.