SMS:Roughness Options Dialog

RMA2 Roughness Options dialog

The RMA2 Roughness Options dialog is used to define the RD card: Automatic Roughness Coefficient Assignment by Depth. See the RD card description in the RMA2 model documentation for more information. This dialog is reached through the Global Methods tab of the RMA2 Model Control dialog.

The following parameters can be set in the Roughness Options dialog:

• Manning's n, no vegetation – Maximum roughness value for non-vegetated water. A positive value will override the default.
• Depth for no vegetation– Depth at which vegetation effects roughness. A positive value will override the default.
• Manning's n, with vegetation – Roughness value for vegetated water. A positive value will override the default.
• Roughness coefficient – Roughness by depth coefficient. A positive value will override the default.
• Minimum Manning's n – Minimum allowed roughness. Default is 0.01.
• Maximum Manning's n – Maximum allowed roughness. Default is 0.20.
• Set Defaults – Opens the Roughness By Depth Defaults dialog. Defaults from several Army Corps projects can be automatically entered into the Roughness Options dialog.

The Roughness By Depth Defaults dialog has the following options:

• "Mississippi River Delta Defaults"
• "S-shaped River Example Defaults"
• "San Francisco Bay Estuary Defaults"

The Roughness By Depth Defaults dialog

After setting the dialog options, a graph of the depth vs. roughness is calculated using the given parameters and shown in the Roughness Options dialog.

Related Topics

• RMA2 Model Control dialog
• RMA2