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cameronParticipant
Have you thought of using HEC-RAS 5.0 for the sediment transport model? in 5.0, you can do sediment transport in Unsteady.
cameronParticipantThe message you show is just a warning and the model will still run. I checked the model you provided and I had to set a few parameters as they were missing (starting date and time, breach time, and adjust weir). You also have the geometry in a folder and not in the same location as the prj file which HEC-RAS might have issues with.
The model goes unstable and I am not sure there is much you can do as your cell size is 0.05m and the min time step is 0.1 seconds. Generally it is a good idea to be close to the Courant criteria especially when dealing with a breach. I would also recommend using the full momentum and not the diffusion wave since breaches have very dynamic flow.
cameronParticipantIn version 5.0 you can create terrain from your cross-sections and then merge them with your DEM. Otherwise you will have to modify it the DEM in GIS or another program.
cameronParticipantI had no problem creating elements, but I am using a March version.
cameronParticipantIf you changed the cross-section data by excavating it, you will need to modify the terrain used in Geo-RAS to match or else the floodplain may not look correct when mapping.
cameronParticipantDoes the jpg have a world file associated with it? Do the xy coordinates in the geometric data editor match the coordinates in Mapper?
Can you post your files for me to look at?
cameronParticipantIf you cut a cross-section from the DEM, does it match what is in the HEC-RAS model?
June 14, 2015 at 7:18 am in reply to: SOLUTION SOLVER FAILED! Unstable for Initial Iteration at 31JUL2010 2400 #9355cameronParticipantThe model is crashing based on your initial conditions. You set these in the unsteady flow data editor in the initial conditions tab. Generally the initial conditions should be set so they match the flow of your inflow hydrograph.
If you are still having problems after this, you can try a ramp up or hotstart to help stay stable.
cameronParticipantThe terrain data for Bald Eagle and Muncie are provided with the beta version.
cameronParticipantI get the same issue, but if you swap the boundary conditions it will run (downstream has inflow and upstream has normal depth).
cameronParticipantWas the result grids based on the bounding polygon shown or something else? Normally no water should be displayed outside of the bounding polygon.
Have you tested looking at the results in HEC-RAS 5.0 in the Mapper? It is far easier than using GeoRAS.
cameronParticipantDo you have levees in your model? Levees adjust the boundary polygon like you have shown.
cameronParticipantIf you post your files, I will take a look.
cameronParticipantWhat you need to do is to use the move points option under the edit pull down and move the end of the tributary onto the the main reach. A window will pop up asking if you want to join them, you can then input the junction information.
cameronParticipantThe best thing you can do currently is export out the results as a raster and do a comparison in another program by subtracting them.
You can also select each element in mapper and get results. Another option would be to use the result data in the hdf file, but it can be confusing if you have not dealt with that format before.
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