﻿  split panel
Manufacturing Solutions

# Split panel

### User Profiles:

Incremental_LS-DYNA

Die Module

Use the Split panel to split plates or solid elements.  In addition, hexa elements can also be split using a technique that moves progressively through a row of elements in the model.

 Note: When you split or refine shell elements, any 1-D elements such as bars that share connectivity with the shell elements will also be split in order to avoid discontinuities in the model.

## Subpanels and Inputs

The Split panel contains the following subpanels and command buttons:

 Plate Elements

### Examples

 Elements are selected Plate elements are split

### Action

elems selector

Select elements to split.

use inferred surface if no geometry exists

When elements are split using this function, the new nodes that are created are placed on the element’s underlying geometric surface, if it exists. If there is not a geometric surface, the new nodes are placed midway between the original corner nodes unless the use inferred surface if no geometry exists checkbox is activated, in which case the new nodes are placed upon the inferred surface of the elements.

Reverse split direction

Reverses the direction quad elements are split.

Only available for when divide quads is selected.

split method options

Select a split method.

 • Split all sides splits a element at the midpoint of its sides.

 - Shortest diagonals splits quad element into tria elements using the shortest possible diagonal.

 - Aligned diagonals aligns the diagonals of all the tria elements in the same direction.

 - Unionjack diagonals splits quad elements into tria elements so that their diagonals create a unionjack pattern.

,

 - Largest angle diagonals splits quad elements into tria elements using the largest angle diagonal.

 • Midpoint - to quads partitions an element by creating a node at its centroid and then forming quads using the midpoints of each of its sides.

 • Midpoint - to trais partitions an element by creating a node at its centroid and then forming trias using the element's nodes.

When you split elements whose nodes are associated to a surface, the new nodes created are also on the surface. To associate a node to a surface, use the Node Edit panel.

All split operators work on both first and second order elements.

split all connected 1D

Splits a connected 1D element at the midpoint of its sides. This option is only available when the split method split all sides is selected.

 Solid Elements

### Examples

 Elements are selected Elements are split into hexas.

### Action

elems selector

Select the elements you want to split.

split method options

The three available patterns include:

 • Splitting the solid elements into hexas
 • Splitting the solid elements into a minimal number of tetras
 • Splitting the solids into symmetric sets of tetras suitable for CFD

When you split elements whose nodes are associated to a surface, the new nodes created are also on the surface.  To associate a node to a surface, use the Node Edit panel.

All split operators work on both first and second order elements.

 Hexa Elements

### Examples

 Elements are selected Select opposing corner nodes on the face of the hexa element to indicate how to split the element. The hexa elements that will be affected by the split command are highlighted. The elements are split.

### Action

hexa element

Select the representative hexa element you want to split.

N1 / N2

Select the nodes.

split method option

Select how you want the element to be split (two pentas, penta and hexa, hexa and penta, two hexas, three hexas, or four hexas).

 Refine Elements

HyperMesh automatically maintains legal connectivity to shell elements that are adjacent to those that are split.

If the refined elements are attached to a surface, HyperMesh makes sure that the new elements are also attached to the same surface.  If they are not, HyperMesh infers a surface from the mesh, and positions the new nodes so that they fall on the implicit surface.

HyperMesh calculates chordal deviation using the algorithm described in the Check Elements panel.

### Examples

 Elements are selected Elements are split using target element size Elements are split using chordal deviation

### Action

elems selector

Select the elements you want to split.

refinement option

Options include target element size and chordal deviation

split all connected 1D

target element edge length

The target element size.

max chordal deviation

The target chordal deviation.

min element edge length

A minimum edge length designating how far Altair HyperMesh is allowed to go while attempting to satisfy the request accuracy.

 Command Buttons

The following action buttons appear throughout the subpanels:

return

Exits the panel.

### How do I...

Refine a mesh of shell elements to a target element size

Refine a mesh of shell elements to a target chordal deviation