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cameronParticipant
You can export out your 1D cross-sections as a terrain in Mapper. You can then create a terrain using the channel surface and the other terrain to create a combined terrain.
The 1D terrain export allows for the entire cross-section or just between the bank stations. If you turn on the XS interpolation layer in Mapper, you will see what the terrain will cover (not the elevation values). In some cases you may need to create interpolated cross-sections to make a better interpolation layer.
cameronParticipantYou can do dynamic viewing (animations in Google Earth) with rasters. There is not an automated way to do in in Mapper though and would require some programming.
cameronParticipantDid you try extending the inflow across the entire inflow boundary?
The model treats the inflow/outflow lines as cross-sections in which it then calculates the wse based on slope and Manning’s.
cameronParticipantthe slope of the river near the boundary is a good first estimate of the energy grade slope.
October 7, 2017 at 2:50 am in reply to: Where to draw 2D flow areas relative to 1D cross sections? #10922cameronParticipantFor this cross-section I would say it is safe to draw it just outside the banks
cameronParticipantWhat are you modeling that requires less than 1ft elements?
cameronParticipantdid you open the vrt or the tif file?
You should be able to open it in Arcmap.
cameronParticipantIf you save out the raster from Mapper as a geotif you could then extract the x and y of the center of each raster cell.
cameronParticipantThe velocity in x and y is an output option for HEC-RAS under the Output Options so there is nothing to do in HDF.
cameronParticipantcould you post the model somewhere?
cameronParticipantYou need to make sure your time step is set up correctly for the mesh size you use.
cameronParticipantdid you specify a grid number size? does the terrain cover the entire grid area?
cameronParticipantYou would need to find another terrain source to merge in HEC-RAS. If you use GIS, you could have it interpolate over the missing area or merge it with other terrain.
cameronParticipantHEC-RAS interpolates between cross-sections and does not use a single xs until the next xs. You would need additional xs to account for the roughness changes. I would just add additional xs 1 ft away for the areas where roughness is changing.
cameronParticipantLook at the 2D user manual for HEC-RAS, Document TD-39 by HEC, and the example 2D files that come with HEC-RAS.
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