Sometimes you may wish to analyze the geometric quality of a mesh that has been generated by the automatic mesh generator in order to get a feeling of how accurate the solver can perform this task. This is necessary because the mesher has to work with overall quality measures. For example, you can have a mesh that contains almost ideal tetrahedra but one element is reduced to a sliver element. In such a case, the quality of the solution may be poor; especially if the element in question sits in a region of interest. The geometric quality of a tetrahedron is calculated from the ratio between the inner sphere and the outer sphere of the tetrahedron. For a tetrahedron of equal-lengthed edges, this ratio is 1:3. This defines a quality value of 1.
To visualize the geometric mesh quality,
1. In the Output group, click Mesh to display the Mesh Output dialog box.
2. Click Use Color under Element Quality.
• If you click Use Color and accept the defaults (Bad and Good), Creo Elements/Direct Modeling generates a VRML file containing the mesh elements with colored faces according to the following coding scheme:
Category
Quality Value
Good
=0.5
Medium
=0.2
Poor
=0.1
Bad
<0.1
• In this case, all elements will have colored faces.
• If you are interested only in elements of a certain quality or a range of qualities, use the Min Quality and Max Quality boxes to specify what you want to see. For example, if you do not want to see the good and medium quality elements, select Poor for the Max Quality.
The elements matching the quality criteria are written to the VRML file with colored faces. The other elements are represented by their wire edges only.
• If you clear Use Color, Creo Elements/Direct Modeling writes the VRML file with the mesh elements having green faces.