Refines, or subdivides, elements. This applies only to triangular surface elements, quads, and tetra elements. While refining triangular surface elements, if tetra elements are connected to the tri surface elements, the tetra's edges connected to the tri's will be subdivided so that the mesh remains conformal. Similarly, refining tetra elements will subdivide adjacent tetra or tri element edges so that the mesh remains conformal.

Coarsens a tetrahedral or tetra/prism hybrid mesh. Elements in the mesh will be coarsened by collapsing edges (merging nodes) and removing degenerate elements, but no operation will be performed that would yield an element with an aspect ratio worse than what is specified. The degree of coarsening (number of elements before vs. number of elements after) is automatically determined and reported in the message window. Disconnected vertices are automatically deleted after coarsening.