Check Elems Panel

1D rigid elements that build loops are highlighted. Rigid elements are detected as forming a loop if the rigid elements form a closed loop and the dependent node of one rigid serves as independent node of the next rigid in the loop.

If memory requirements are exceeded, reduce the number of displayed rigids.

When this checkbox is cleared, 1D elements that share the same dependent node are considered to fail this check. Thus a rigid element whose dependent node is an independent node of another rigid element does not fail this check.

Skew in quads is calculated by finding the minimum angle between two lines joining opposite mid-sides of the element. Ninety degrees minus the minimum angle found is reported.

2D elements

$A_i$ = unit vector, normal to cell edge i

$r_i$ = vector connecting the cell centroid and the middle edge i

3D elements

$A_i$ = unit area vector, normal to cell edge i

$r_i$ = vector connecting the cell centroid and the centroid of face i

A circle is generated through the three corner points of the actual triangle. This circle defines a ideally shaped tria elements, from which the area is computed, A_ideal. The area from the actual triangle is computed as well, A_actual. The area skew is defined as: Area skew = (A_ideal-A_actual) / A_ideal.

Figure 1. Example: Taper

Triangles are assigned a value of 0, in order to prevent HyperMesh from mistaking them for highly-tapered quadrilaterals and reporting them as "failed".

Skew in quads is calculated by finding the minimum angle between two lines joining opposite mid-sides of the element. Ninety degrees minus the minimum angle found is reported.

Tetra collapse calculation: At each of the four nodes of the tetra, the distance from the node to the opposite side of the element is divided by the square root of the area of the opposite side. The minimum value found is normalized by dividing it by 1.24, and then reported. As the tetra collapses, this value approaches 0.0. For a perfect tetra, this value is 1.0.

• $A$ = face unit area vector
• $\left|r_c\right|$ = 2D elements: vector connecting the adjacent cell centroids
• 3D elements: vector connecting the cell centroids and the cell face centroid

Within cells

Normalized dot product of the area vector of a face and ve3ctor from centroid of the face.(1)

$$\frac{\overrightarrow{Ai}\cdot \overrightarrow{f}i}{\left|\overrightarrow{A}i\right|\left|\overrightarrow{fi}\right|}$$

Across cells

Normalized dot product of area vector of a face and vector from centroid of cell to neighboring cell centroid.(2)

$$\frac{\overrightarrow{Ai}\cdot \overrightarrow{c}i}{\left|\overrightarrow{A}i\right|\left|\overrightarrow{ci}\right|}$$

Volumetric skew calculation: A sphere is fit through the four nodes of the tetra. That sphere defines an ideally shaped equilateral tetra, whose volume is $8r^3/\left(9\sqrt{3}\right)$ . The actual volume of the tetra element is then calculated.

The element's volumetric skew is then (Videal -Vactual)/Videal. This measure will, normally, equal the skew measure from Tgrid, and equal 1 minus the equivalent check in Abaqus.

Vol AR calculation for tetrahedral elements: The longest edge of the tetrahedron is found first, then the shortest altitude of the tetrahedron is found. The element's Vol AR, then, is the length of the longest edge divided by the length of the shortest altitude. For other types of 3D elements, the ratio of the longest to the shortest edge is reported.

Checks can be carried out separately for shell and solid elements, for spring and beam elements, or all element types.

To be used with the assign plot display plot.

2D elements that share more than one edge (two connecting nodes form an edge of a first order element; two corner nodes and one mid-side node form an edge of a second order element) with another two-dimensional element are highlighted.

3D elements that share more than one face with another three-dimensional element are highlighted.

Any elements where there are mid-side nodes connected to corner nodes are highlighted.

This operator can be used to find duplicate elements.

If an element is duplicated, the elements involved are highlighted, except for the element with the lowest ID.

Duplicates can be deleted by clicking save failed and then retrieving the user mark (using extended entity selection) in the Delete panel. The saved (failed) elements can be accessed in any other panel using the retrieve option in the extended entity selection menu.

When you use this function, elements that were previously on the user mark are replaced. Once the failed elements have been saved, the user mark can be loaded into other panels.

The saved (failed) elements can be accessed in any other panel using the retrieve option in the extended entity selection menu.

standard (default)

Elements that exceed the specified criteria are highlighted.

assign plot

Create a color-coded view of the model, with each element or contour bearing a color based on how well or poorly it conforms to the selected check criterion. Visual options alter the rendering style (hidden line or wireframe), color method (by element or by contour), model lighting, and mesh line visibility. Create a cutting plane to view a cross-section of the model.

histogram

Graph the percentage of elements on the X axis and their deviation from the specified criterion on the Y axis. Click reset visual to clear the graph and return it to the model view.