Grid

The grid in this example is obtained with the onedgrid.m m-file which can be downloaded from

http://suntans.stanford.edu/downloads_stanford .

In this case, the grid contains 200 cells in the horizontal and 20 in the vertical, with a length of 100 m and a depth of 20 m. This constant depth is specified in initialization.c in the function ReturnDepth with the line

return 20;

Note that in order for this depth to be specified, the IntDepth parameter must be set to 0 in the suntans.dat parameter file. As shown in Figure 8, this grid is stretched in the vertical in order to provide extra resolution at the bottom boundary. This is done by specifying a negative stretching factor of $r=-1.025$ (suntans.dat: rstretch = -1.025), which causes each grid layer to be 1.025 times thicker than the layer beneath it.

Figure 8: Depiction of the vertically stretched grid for the lock exchange problem. Every fourth vertical cell face plotted for clarity.

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