NOTE: not tested or fully implemented, but will be something like this
Assigns a river flux boundary condition, as described in Section 3.7.1 to nodes in the specified set. These nodes are normally located on the surface of the domain. For river flux nodes, water may flow in or out of the domain depending on the difference in head between the river node and the specified river head value.
The following instructions can be used as input to the Type instruction inside the Boundary condition...End instruction group to assign a river flux boundary condition:
Sets the input type to be a river flux drainage boundary condition.
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boundary condition type simple river node set my_river time value table 0.0 1.e-5 25. end end
This example shows the use of a time value table instruction to define the river conductance (1.e-5) and river head (25.) values. This would not be very useful in most cases, since conductance and head vary from node to node along a river. In such cases, the inputs would be defined by a time file table, with unique values given for each node:
boundary condition type simple river node set my_river time file table 0.0 my_river.lst 1000. none end end
Here, the river flux boundary condition would become inactive after time 1000 and the nodes would become unconstrained. In this case, the file my_river.lst would contain two values per line, the river conductance and head value, and one line for each node in the set.
NOTE: In the old instruction for defining river fluxes, there were inputs for bed thickness, bed conductance, reach length and reach width which were then used to compute a river conductance term. Now, it is left up to the user to define the conductance term in any way they see fit, and to write the final conductance value into the input file.