Generate Grid Dialog Box

The Generate Grid dialog box is used to help control the generation of a grid using objects (p. 12).  It is displayed by selecting Grid|Generate Grid... or clicking the Generate grid button . Before it can be used, there must be at least one polygon on the top view of the model for which Use to set element grid size is true. For PHAST models, there must also be at least one polyline or polygon on the front or side views of the model for which Use to set element grid size is true. (See the Object Properties dialog box.) The Calculate grid angle automatically checkbox determines whether or not ModelMuse will calculate a grid angle or use an angle supplied by the user. If ModelMuse calculates the angle automatically, it will specify the angle so that the area of the grid is minimized. If it is not calculated automatically, the user must specify the grid angle (in degrees) in the Grid angle edit box.

Some groundwater-modeling programs benefit from keeping the contrast in the width of adjacent cells less than a value of 1.5 (Anderson and Woessner, 1991). This can be achieved by checking the Smooth grid checkbox in the Generate Grid dialog box. If it is checked, the checkboxes for rows, columns, and layers determine whether grid smoothing will be applied in those directions. The Grid smoothing criterion determines the maximum ratio allowed between adjacent elements.

For computing a well footprint, the cells must be of uniform size so only one object will be used to set the cell size and the Grid smoothing criterion has no effect. (See WellFootprint Properties dialog box.)