Description
Boundary Control Functions are used to influence the distribution of grid points near the grid boundaries. They are calculated by adjusting the control functions locally so the grid points one layer inward from the boundaries will satisfy a specified spacing and angle constraint, with all other interior points blended smoothly.
Spacing constraint refers to the distance between a boundary grid point and the grid point one layer inward, and angle refers to the angle that the grid line between these two points makes with the boundary itself.
Use the Type pull down list to select the desired Boundary Control Function to use: Steger-Sorenson, von Levante-Hilgenstock-White, or None.
The available boundary control function types are:
- von Lavante-Hilgenstock-White: Applies the von Lavante-Hilgenstock-White (Ref. 10, Ref. 39, Ref. 41) boundary control function formulation to the selected boundaries. This method yields virtually exact enforcement of the constraints but the grid may lack some of the smoothness provided by Steger-Sorenson.
- Steger-Sorenson: Applies the Steger-Sorenson (Ref. 23) boundary control function formulation to the selected boundaries. The resulting grid is smooth, clustered, and orthogonal at the boundaries. However,the constraints are only maintained in an approximate sense, especially in concave regions. This method is the default.
- None: Does not apply a boundary control function on the edge.