Time varying SZ drainage parameters
In projects where you want to simulate the build out of an SZ drainage network over time, or changes in the SZ drainage time constants over time, then you can use this set of extra parameters. Without this set of extra parameters you would have to hot start your simulation at regular time intervals with the new SZ drainage parameters.
The time varying SZ drains are also allowed to shift between layers. However, if the SZ drainage level goes above or below the model, the level will be adjusted and a warning is issued to the log file.
Note: The SOR solver does not allow drainage in any layer except the top layer and the drain level will be adjusted accordingly.
Note: If you specify time varying SZ drainage parameters, you will not be able to use any of the drainage routing methods that depend on the drain level. The preprocessor checks this and gives an error if you have specified
· option 1 (routing based on levels), or
· option 3 (distributed options) AND any of the distributed option codes are 1 (routing based on levels in these cells).
To activate time varying SZ drainage parameter options, you must specify the following extra parameters
|
Parameter Name |
Type |
Value |
|---|---|---|
|
time varying drainage levels |
Boolean |
On |
|
time varying drainage time constants |
Boolean |
On |
|
drainage level dfs2 file name |
file name |
.dfs2 file |
|
drainage level item number |
integer |
item number in dfs2 file, greater than zero |
|
drainage time constant dfs2 file name |
file name |
.dfs2 file |
|
drainage time constant item number |
integer |
item number in dfs2 file, greater than zero |
|
Optional: |
||
|
mean step accumulated drainage levels |
Boolean |
On |
|
mean step accumulated drainage time constants |
Boolean |
On |
The dfs2 Drain Level is an elevation that can be specified using the following three EUM Data Units (V1 p. 135):
· Elevation
· Depth Below Ground (i.e. positive values)
· Height Above Ground (i.e. negative values)
By default, the Time Series Types (V1 p. 147) is Instantaneous, but there is an extra option that allows you to used Mean Step Accumulated values if you want. The use of Mean Step Accumulated does not change the meaning of the item, but changes the way the values are interpolated.
Note: The code does not check for the time series type.
All specifications are printed to the projectname_PP_Print.log and projectname_WM_Print.log files.
