Moldflow

These checks apply to both types of elements, but when applied to 3D elements they are generally applied to each face of the element. The value of the worst face is reported as the 3D element’s overall quality value.

Aspect Ratio

Only applied to triangles, with quadrilaterals given a value of:

$$\frac{2.0}{\sqrt{3}}$$

This is the same value obtained from an equilateral triangle, and is assigned to quads to prevent HyperMesh CFD from misinterpreting a quad as a badly formed triangular element.

Moldflow calculates a triangle’s aspect ratio by squaring the longest edge of the triangle, and dividing the result by twice the triangle’s area. 1.0 denotes a perfect equilateral triangle.

When applied to 3D elements, the aspect ratio is the ratio between the longest and shortest edges of the tetrahedral element.

Vol. Aspect Ratio

Finds the perpendicular height h of each node, and then dividing the longest edge length L by the shortest height h and multiplying by the square root of 1.5:

$$\frac{\sqrt{1.5}\times L}{h}$$

This results in an equilateral tetrahedron having a volume aspect ratio of 1.5. Non-tetrahedral elements are assigned a value of 1.0.