Aspect Ratio (Explicit ) is the ratio of the longest edge of an element to its shortest edge or it is the shortest distance from the corner node to its opposite edge. For calculating the aspect ratio of 3D elements, each face of the element is treated as 2D element to determine the aspect ratio and the largest aspect ratio among the faces is considered as the aspect ratio for the 3D element.
The Aspect Ratio is calculated as follows:
AR= lmax/min(l,h*)
where,
lmax is the maximum edge length.
lmin is the minimum edge length.
l is the linear edge length
h is the height of the node to the non-connected face edges
hmin is the minimum face height
hmax is the maximum face height
h* is the normalized height
For triangular elements, the normalized height is calculated as
h*=2/sqrt(3)*h
For quadrilateral elements, the normalized height is
h*=h
For tetrahedron elements, Aspect Ratio (Explicit) is the ratio of longest edge of an element to its shortest height measured from a node to its opposing face.