SMS:ADH Boundary Condition Assignment

To open this window, at least one node or nodestring must be selected. After a selection is made, select the ADH | Assign BC... menu item or use the right-click menu.

ADH boundary conditions consist of two specification types (Dirichlet and Natural) and three condition types (flow, pressure, and transport). Dirichlet data is applied on the domain to individual nodes or to groups of nodes (defined with nodestrings). Natural data (flux) is applied through edges of the domain defined by nodestrings and includes a friction specification. A node or nodestring can be assigned only one condition option from each of the three condition types (two flow conditions cannot be assigned to a single node).

Boundary Conditions

Flow Condition Options	Specification Type	Information
None	---	No condition specified
Flow (per unit length)	Natural	Specified by a Flow (per unit length) time series; NB OVL card with a friction card
Sidewall (no through flow)	Natural	Creates a vertical wall with the specified shear stress; just a friction card
Subcritical inflow	Dirichlet	Specified by a Velocity time series; DB OVL card
Supercritical inflow	Dirichlet	Specified by a Depth time series and a Velocity time series; DB OVH card
Tailwater (outflow)	Natural	Specified by a Water Surface Elevation time series; NB OTW card with a friction card
Total discharge	Natural	Specified by a Discharge time series; NB DIS card with a friction card

Pressure Condition Options	Specification Type	Information
None	---	No condition specified
Lid (depth underneath)	Dirichlet	Specified by a Depth time series; i.e. a structure (ex. culvert, sluice gate, etc.) defined using bed elevation as datum; DB LDH card
Lid (draft)	Dirichlet	Specified by a Draft time series; i.e. a floating object (ex. boat, dock, etc.) with draft; DB LID card
Lid (elevation)	Dirichlet	Specified an Elevation time series; i.e. a structure (ex. culvert, sluice gate, etc.) defined using the elevation datum; DB LDE card

Transport Condition Options	Specification Type	Information
None	---	No condition specified
Dirichlet	Dirichlet	Specified by a Transport time series; DB TRN card
Equilibrium	Dirichlet	Specified by initial concentration (in ppm); This condition can only be assigned to sediments and specified in simulations without cohesive sediments; EQ TRN card
Natural	Natural	Specified a Transport time series; NB TRN card

Weir Options	Specification Type	Information
None	---	No condition specified
Weir		Nodestrings are specified as upstream, upstream edge, downstream or downstream edge. See the WER and WRS card

Natural Flow Condition Friction Options

Friction Options	Information
Manning's n	Specified by a roughness value; FR MNG card
Equivalent roughness height	Specified by a roughness height (in ft or m); FR ERH card
Submerged aquatic vegetation	Specified by an undeflected stem height (in ft or m); FR SAV card
Un-submerged rigid vegetation	Specified by a roughness height (in ft or m), averaged stem diameter (in ft or m), and average stem density (in stems/ft² or stems/m²); FR URV card

All mesh boundary edges that do not have a boundary condition will be treated as a frictionless sidewall with no through flow.

All boundary conditions listed above can only be assigned to the mesh boundary, expect the pressure conditions which can also be assigned to the mesh interior.

When changing a condition type on any tab, the existing condition information is cleared from the window such that the information must be respecified upon returning to that type.

Dialog Description

The following controls specify the boundary condition to be assigned to the currently selected entities. This window is expandable by dragging the window edges to increase visibility of the spreadsheet data on the Transport tab.

Boundary Condition Type (Tab Control)

This tab control can contain the following three tabs:

Flow

This tab is only available if all of the currently selected nodes or nodestrings are on the mesh boundary.

Boundary type combo box contains the conditions available for flow (listed above) for the selected entities.

Series data curve button selects the time series to be associated with the selected boundary type. The text label above this curve button will change with the boundary type to denote the type of input. Clicking on the curve button will open the Time Series editor (limited to the curve group of the boundary type). A second curve button will appear for boundary types that require two conditions with time series data.

Friction combo box specifies the type of bed shear stress to be applied to the boundary edge and is available only for Natural boundary types. The friction options are:

• Manning's n provides the Manning's n roughness real number edit field limited to a value of 0.0 to 0.3.
• Equivalent roughness height provides the Roughness height positive real number edit field.
• Submerged aquatic vegetation provides the Undeflected stem height positive real number edit field.
• Un-submerged rigid vegetation provides the Roughness height, Average stem diameter and Average stem density positive real number edit fields.

Pressure

This tab is always available.

Boundary type combo box contains the conditions available for pressure (listed above) for the selected entities.

Series data curve button selects the time series to be associated with the selected boundary type. The text label above this curve button will change with the boundary type to denote the type of input. Clicking on the curve button will open the Time Series editor (limited to the curve group of the boundary type).

Transport Constituents

This tab is only available if all of the currently selected nodes or nodestrings are on the mesh boundary and constituents have been included in Transport Constituents.

Boundary type combo box contains the conditions available for transport (listed above) for the selected entities.

Spreadsheet contains the following information specific to each transport type:

• None clears the display of any information in the spreadsheet.
• Dirichlet provides each defined constituent (first column) with a Include check box (second column), Specify Series... curve button (third column), and a series name cell (fourth column). To include the constituent in the specification of the transport condition, check the Include control and specify a concentration series by clicking on the Specify Series... button which will open the Time Series editor (limited to the Transport curve group). When a series has been defined, the name will be listed in the series name cell. A series can be selected by multiple constituents. The concentration series button and name cells are only enabled if the constituent is included in the transport source.
• Equilibrium provides each defined sediment (first column) with a Include check box (second column) and a positive real number Initial concentration cell (third column). To include the sediment in the specification of the transport condition, check the Include control and specify a concentration (in parts per million). If the sediment is not to be present at the beginning of the simulation, specify a concentration of zero. The Initial concentration cell is only enabled if the sediment is included in the transport source.
• Natural provides the same as Dirichlet.

Output (untitled group box)

Output calculated flow across this entity check box is available only for nodestrings and correlates to the FLX card.

Related Topics

ADH