Creating at least two elements through the thickness of tetrahedral meshes

In the 3D Tetrahedral Mesh dialog box, you can use the Minimum Two Elements Through Thickness option to ensure that the software creates a solid mesh that is at least two elements thick through very thin regions of an otherwise thick or chunky part.

The following graphic shows a model of an optical support structure with a tetrahedral mesh where the overall element length is 4 mm. Notice the difference in thickness between the thin, ribbed regions and the rest of the part. (1) shows the mesh with the Minimum Two Elements Through Thickness option turned off. (2) shows the mesh with the Minimum Two Elements Through Thickness option turned on. Notice how the mesh in (2) is 2 elements thick along the thin ribs.

The Minimum Two Elements Through Thickness option is useful when you want to specify a large element size for the overall mesh still ensure that the mesh on any thin-walled regions will be at least two elements thick.

Common uses

The Minimum Two Elements Through Thickness option is useful when:

• Your part is a solid body with both thin wall regions and chunky wall regions, where the thin wall regions are extensive and exhibit plate-like responses to static or dynamic loadings.

• You are generating a 3D mesh on the part because you were unable to create a satisfactory midsurface.

Understanding how the software creates a minimum of two elements through the thickness

When you select the Minimum Two Elements Through Thickness option, the software:

• Searches the part for surface feature angles that are characteristic of the thickness differences. Based on the surface feature angles, the software determines which regions are thin relative to the rest of the body.Note: The software does not perform a thickness survey of the entire solid body.

• Identifies surfaces that represent the walls of the body in thin regions and generates at least two elements through the thickness of the mesh in those areas.

Mesh quality

The Minimum Two Elements Through Thickness option can negatively impact the quality of the 3D mesh in the thin regions. For example, because the software subdivides the elements to achieve the goal of having two elements through the thickness, the aspect ratio of the resulting tetrahedral elements increases. This means that the aspect ratio of elements in a 3D mesh where the Minimum Two Elements Through Thickness option is selected is higher than in a 3D mesh where the Minimum Two Elements Through Thickness option is cleared.

Where do I find it?

Application	Pre/Post
Prerequisite	FEM is the displayed part and work part
Command Finder	3D Tetrahedral Mesh

How do I

Create a 3D tetrahedral mesh

Learn more

3D tetrahedral meshing

Understanding the tetrahedral meshing process

Understanding 3D tetrahedral mesh quality evaluation

Midnode placement for parabolic elements

Understanding the Auto Fix Failed Elements process

Controlling the size of interior elements in a 3D tetrahedral mesh

Quick links

Command reference

Pre/Post video examples

Bulk Entry Descriptions

Simcenter 3D tutorials

Browse Simcenter 3D help by product area

Creating at least two elements through the thickness of tetrahedral meshes, Simcenter 3D 2021.1 Series

© 2020 Siemens

window.mainLanguage="en_US"

window.delivId=""

window.projectId=""

MathJax.Hub.Config({ TeX: { extensions: ["autoload-all.js"] }, tex2jax: { displayMath: [ ] }, "SVG": { scale: 125 } });