Water Level Boundaries
|
|
HS
|
Sinusoidal (Tidal) Water Level (m)
|
A sinusoidal wave based on any number of constituents. At present, HS boundaries must be entered using the fixed field approach (see Section E.3).
|
HQ
|
Water Level (Head) versus Flow (m)
|
Assigns a water level to the node based on the flow entering the node. This boundary is normally applied at the downstream end of a model.
|
HT
|
Water Level (Head) versus Time (m)
|
Assigns a water level to the node based on a water level versus time curve. If other HT or HS boundaries are applied to the node the water level is set to the sum of the water level boundaries.
|
HX
|
Water Level (Head) from an eXternal Source (ie. a 2D domain)
|
Not required anymore. Was previously used to indicate that a 2D SX boundary is linked to the 1D HX boundary node. This is now determined automatically from 2D SX boundaries.
|
Treatment
|
Nodes can be wet or dry. If the water level is below the bed, the bed level is assigned as the water level to the node.
As the water level in the node is defined by the boundary, the node’s storage has no bearing on the results.
|
Combinations
|
Any number of water level boundaries can be assigned to the same node. The water level used is the sum of the water levels assigned. For example, a storm tide may be specified as a combination of a tidal HS boundary, a HT boundary of the storm surge and another HT boundary of the wave setup. Clearly the HS boundary would be water elevations and the two HT boundaries water depths.
The exception is that a HX boundary, being a dynamically linked one, cannot be summed with another H boundary. If you have a 2D SX boundary connected to a node (this automatically applies a 1D HX boundary to the node) and also have a HT and/or HS boundary at the same node, the 1D HX boundary prevails and no warning is given.
|
Flow Boundaries
|
QC
|
Constant Flow (m3/s)
|
A constant flow boundary. At present, QC boundaries must be entered using the fixed field approach (see Section E.5).
|
|
