Controlling mesh size with edge factors

You control mesh size with two primary inputs: Min Edge Factor (Fmin) and Max Edge Factor (Fmax). These factors are multiplied by the part’s slice height to obtain the minimum and maximum edge lengths used by the mesher. They determine both refinement and element quality.

For both surface remesh and volume mesh:

Max edge length, Lmax = Fmax × h

Min edge length, Lmin = Fmin × h

Average edge length, Lavg = (Lmin + Lmax) / 2

where, h is the slice height.

Edge length is the length of an edge on the surface triangulation generated before volume meshing. Average edge length is derived from min and max; it is not a separate typed input.

NoviPath suggests default Fmin and Fmax values from an estimate of how many tetrahedra will fit in the part’s bounding box. A typical recommended Fmin is 2. The software may recommend higher factors (a coarser mesh) if the part is too large to solve comfortably on a computer with 8 GB of RAM. You can still choose more aggressive factors than the recommendation when you need a finer mesh.

Tip: For element quality, keep Min Edge Factor close to 2. For a more refined mesh, tighten the range (Max − Min).

Tip: For highly curved or thin-walled parts, widen the range. A larger range lets the mesher place smaller tetrahedra in curved or thin regions and larger tetrahedra elsewhere.

Mesh sensitivity and Example: mesh refinement on a thin-walled clamp show, on a real part, how the edge factors change element count, run time, memory and the predicted results.