Other mesh treatments

The are functions for special treatments of meshes. The current version of VisualFEA supports 2 functions: creating a crack tip and remeshing.

> Remeshing

A selected part of a surface mesh can be remeshed. Automatic mesh generation algorithms are used in remeshing operation.

	1) Click the element selection tool , if it is not in pressed state.
	There appears menu at the right end of the menu bar. "Select Surface Elem." item of the menu should be checked.
	2) Select the region of elements to remesh.
	The selected elements should be within a surface mesh and form a unified region. Otherwise, remeshing will not work.
	3) Choose "Remesh" item from submenu.
	If all the selected elements have quadrilateral shape, quadrangle elements are generated by remeshing. Otherwise, triangular elements will be generated.

< Example of remeshing >

Remeshing cannot be undone, and therefore the original mesh cannot be recovered. It is a good strategy to save the model before remeshing, so that the original mesh can be recovered in case the remeshing produces unsatisfactory result.

> Making crack tip elements

The stress singularity at a crack tip is usually modeled by using quarter point elements in which the mid-side nodes are positioned at one quarter of the edge length from the crack tip node. The elements surrounding a crack tip can be converted into quarter-point crack tip elements by the following steps:

	1) Click the node selection tool , if it is not in pressed state.
	2) Select the crack tip node.
	The crack tip node should be at the tip of the crack, and the surrounding elements should be of quadratic order i.e., 6 node triangular or 8 node quadrilateral element.
	3) Choose "Remesh" item from submenu.
	The surrounding elements are converted into quarter point crack tip elements. The mid-side nodes of the elements move to the quarter points along the edges toward the crack tip.

<Example of creating crack tip elements >