Description

For blocks only, vertex-centered orthogonality is computed as an area-weighted average of the orthogonality angles associated with each bounding face of the dual mesh control volume around the vertex. For more information on how volume cells are subdivided into sectors to form the dual mesh control volume, see the page on Vertex-Centered Volume.

The orthogonality angle (shown in red in the diagram below) for a volume cell's edge is computed as the angle between the unit edge vector (represented as the solid black arrow) and the quadrilateral defined by the edge midpoint, the adjacent face centroids, and the volume centroid. This quadrilateral belongs to the boundary of the dual mesh control volume for both vertices in the edge.

Vertex-Centered Orthogonality
The orthogonality angle (shown in red) for a volume cell's edge (shown in black). The quadrilateral formed by the edge midpoint (blue circle), adjacent face centroids (green squares), and the volume centroid (yellow triangle) belongs to the boundary of the dual mesh control volume for both vertices in the edge.

This metric affects robustness for vertex-centered solvers and ranges from 0 degrees to 90 degrees, with 90 representing perfect orthogonality. For this function, the probe renders the vertex and the bounding faces of the dual mesh control volume.

 

Tip: Use the probe functionality while in the Examine command to visualize the dual mesh control volume when examining any vertex-centered function.