The unstructured domain solver's grid control parameters provided in the Quads frame (see figure below) allow you to establish the criteria by which the solver decides whether and how to combine triangular cells into quads.
Note: The attributes in the Quads frame have no impact if the Algorithm is set to Thin Surface Interpolation. However, they are still used when Thin Surface Interpolation cannot be applied and the Algorithm defaults to Advancing Front Ortho.
When the unstructured domain solver uses either the Delaunay or the Advancing Front algorithms (refer to the Algorithm section for more information), the generation of quad-dominant domains involves two steps: first, the domain is triangulated, and second, the triangular cells are combined to form quadrilateral cells wherever possible. The Quads frame provides tools to decide whether two triangular cells can be combined into a quadrilateral cell.
Quad Max. Included Angle lets you specify the maximum included angle allowed for quadrilateral cells. This parameter prevents the combination of triangular cells if the included angle of the final quadrilateral cell is larger than the specified value.
Quad Max. Warp Angle lets you specify the maximum warpage allowed for quadrilateral cells. This parameter prevents the combination of triangular cells if the warpage of the final quadrilateral cell is larger than the specified value.