Learning Forum

[balias]

Hi Experts 

What does the element size indicate ? When someone say element size of a tetrahedral quadratic element is 2 what should I understand from it ?

https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v192/wb_msh/msh_Element_Size.html

 

This is what I found in help. But what are bounding box diagonal, bounding box factor and surface area factor ?

 

Thanks

[SSURA]

 

Hi @balias,
The element size allows you to set the size for the entire model. It can be used for the edge, surface, and body. Generally speaking, it is the smallest size you want to divide your model into for the analysis. Solver usually specifies the appropriate element size considering the physics preference and characteristics of the model, but if there are regions in the model with particular concerns, setting the mesh controls manually will generate accurate results.

So in order to obtain accurate results, mesh sizing must be appropriate which is relative to the system dimensions. The bounding box diagonal reads the length of the diagonal of the model, by selecting the appropriate factor you can get an appropriate element size. Or it may also depend on the limitation of the nodes. The following video lesson may help you in selecting the appropriate element size.

You may classify the elements on the basis of geometry, formulation, functionality, etc. This is different as per the characteristics of the model or even the physics preference. So the example ‘element size of a tetrahedral quadratic element is 2’, indicates a 3-dimensional element ‘Tetrahedron’ with a quadratic behavior (10 nodes present, 4 at corners and others between them) with a size of 2 units (depends on the unit system).

More information can be found in the following references- 

1. How to Specify an Appropriate Element Size Using Ansys Mechanical – YouTube

2. Meshing Options on the Options Dialog Box (ansys.com)

Hope that helps!
Thanks,
Sahil