HydroGeoSphere/River Flux

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:

Simple river

Sets the input type to be a river flux drainage boundary condition.

• • •

For example:

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.

Notes

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.