Skewness angle
 

Hello everybody,

what is the commen definition of a skewness angle of a tetrahedron? I looked for this for hours and can't find an answer.

Thanks for reading, Chris

Re: Skewness angle
 

For 2D Tria, the property that might grasp our interest is the skewness angle, defined by HM:

skew in Trias is calculated by finding the min. angle between the vector from each point (of the Tria) to the opposing mid-side and the vector between the two adjacent mid-sides at each point of the Tria.

For 3D Tetra, volumetric skew is important, defined by HM: A sphere through the four nodes of the tetra is created. That sphere defines an ideally shaped equilateral tetra, in which its volume is defined as: 8r^3/(9*sqrt(3)). The actual volume of the tetra element is then determined.

The Tetra's volumetric skew is then written as: Volumetric skew =( Videal-Vactual)/Videal

Hope that helps.

-khai ching-

Re: Skewness angle
 

Ok, so I guess the term "Skewness angle" does not exist. I am examining a volumetric grid in Gridgen with that "Skewness - min ang"-Function and wonder which angles are meant. The overall average of those angles is around 45°.

Re: Skewness angle
 

probably the angle between two adjacent edges, or the angle between an edge and the two faces it is not part of ...

Re: Skewness angle
 

Chris, I suggest that you contact a technical support engineer at support@pointwise.com and they will be able to tell you exactly how that skewness measure is calculated.