Setting Roughness By Polygon


I have a 2x2m grid of hydrodynamic roughness values (that were derived from the bathymetry) that I would like to apply to the entire model domain. This file is of the exact spatial specifications as the file used to derive depths using the bathymetry tool. I need to set the roughness value for each grid cell equal to its corresponding value in the import file. I have attempted to use the assign roughness dialog in EE but have had little luck. In these attempts I have specified the model polygon (equal to the polygon that I used to define the active model domain) and have supplied the data file containing the roughness values but to no avail. The dialog box appears to be applying a value to each cell in the model domain but when I look at the roughness option in the plan view nothing has changed. Can someone give me some guidance regarding this need.

Thanks in advance.

Do you mean to provide roughness height different for each cells ? If you want to give roughness into different regions then you may use the polygon tool to that. Make sure you save your model after you modify the roughness. If you just want to make roughness different to some cells you can do so by simply pressing button alt and select the region with the RMC (right mouse click) then you should be able to assign the values on those selected cells. If you need to provide different roughness on each cells then it would take some time.

For this problem, before EE7.0 it was only possible to apply a constant hydrodynamic roughness in each polygon. However, with EE7.0 it is now possible to specify a datafile for hydrodynamic roughness and interpolate it onto model domain (either the whole model domain or a portion of the model domain if a polygon is used in conjunction with the datafile).