Skew angle mesh quality criterion reflects the angle between the lines that join opposite sides of the element. SKEW is a maximum value of all skew angles.
This mesh quality criterion can be applied to elements composed of 4 and 3 nodes (quadrangles and triangles)
To apply the Skew angle quality criterion to your mesh:
1. Display your mesh in the viewer.
2. Choose Quality Controls > Skew or click button of the toolbar. Your mesh will be displayed in the viewer with its elements colored according to the applied mesh quality control criterion: