User's guide of Proceessing Modflow 5.0

214 Processing Modflow
the Grid < Mesh Size… and it is quite easy to add additional rows and columns to an existing
mesh. This is done by using a combination of holding down the CTRL key and using the arrow
keys as follows:
CTRL + Up arrow - add a row
CTRL + Down arrow - remove an added row
CTRL + Right arrow - add a column
CTRL + Left arrow - remove an added column.
It is also possible to specify the row and column spacing of individual cells by clicking the right
mouse button within the cell of interest, however we will not be doing that in this exercise.
< To refine the mesh around the pumping wells
1. If you aren’t already in the Grid Editor, enter by,
Grid < Mesh Size…
2. Zoom in around Well 1 by clicking on the button and then dragging a box around the
general area of Well 1.
3. Change back to the button and click on the cell containing Well 1.
4. Divide this column to three by adding two additional columns
CTRL + Right arrow followed by,
CTRL + Right arrow
5. Divide the row also into three by,
CTRL + Up arrow followed by,
CTRL + Up arrow
You should see dashed lines where the new rows and columns will be placed.
6. Zoom out by pressing the button. You will notice that the rows and columns added
extend throughout the model domain and form part of the fine discretisation around some
of the other wells.
7. Repeat the above refinement around Well 2 to Well 9, remember some of the discretisation
has already been done when you added rows and columns around Well 1.
8. At this stage your cells increase from a size of 167 m to 500 m abruptly, in order to have a
more gradual increase in cell size we need to half the size of the following rows and
columns (again using the CTRL key and the arrow keys).
Columns 3 and 11
Rows 7, 9, 10, 12, 17 and 19
The number of the rows and columns are given in the status bar on the bottom of the screen
and are number such that the cell specified by Column 1, Row 1 is the top left cell of the
model (in a 3D sense the top layer is also Layer 1 with Layer numbers increasing with
6.1.1 Tutorial 1 - Unconfined Aquifer System with Recharge