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cameronParticipant
Was it ever working? I have seen HEC-RAS have issues like this when some of the cross-sections are set up to close together and are different lengths or cross-sections are overlapping.
cameronParticipantAre you talking about 1D or 2D modeling? 1D modeling has the blocked obstruction option. For 2D modeling you would either need to account for the building using a high roughness value or adjust the terrain to account for the building.
cameronParticipantHow does the *.prj file look? Does it contain all of the plan/geometry files?
cameronParticipantAre you running it with the full momentum or diffusion wave solver? Have you tried adjusting your time step?
cameronParticipantThe warnings you are getting are causing some of the problem. The first warning is telling you that the program did not solve for that cross-section and used critical depth for the answer. The second warning is similar. The third warning is stating that the change in conveyance between the two cross-sections is to large and may need more cross-sections. The fourth warning states you may need more cross-sections.
Basically you may need to add/remove cross-sections, adjust roughness values, or modify cross-sections to fix the problem.
cameronParticipantIf you have a TIN in GIS, you need to convert it to a raster using one of the tools in ArcMap or similar. If you have a TIN in Microstation format, I generally convert it to a landxml file, import it into GIS as a TIN, and convert to a raster.
cameronParticipantAre you getting any warnings or errors stating cross-sections are defaulting to critical depth?
cameronParticipantCan you post this model somewhere?
cameronParticipantIt depends on how you are trying to account for the buildings. If you use a roughness value to account for buildings, it will also account for some of the storage in the building. If you use the buildings themselves in the terrain, you will lose that storage. There are many other reasons to include them or not, it just depends on the purpose of the study.
cameronParticipantHave you tried a initial conditions ramp up? The 1D model is the area that needs to be wet, 2D areas can be dry unless a cross-section is connected directly to the 2D area then you need have a continual flow of water from the 1D model to the 2D or the model will crash.
August 5, 2016 at 7:38 pm in reply to: To extract depth & velocity of each computational cell #10023cameronParticipantThe values are stored in the *.p01.hdf file for every. The velocities are computed at corner nodes and depth is at cell center.
cameronParticipantIf you open up the *.p01.hdf file, there is a table that contains the coordinates for the face points, which is what you are looking for. What you could also do is export out the mesh as a shapefile which you could use to get the values.
July 18, 2016 at 4:03 am in reply to: 2D Model with Internal Connections showing more flow than inflow #9996cameronParticipantIs the flow going through the internal connections 2D or 3D? If the connections act like a weir, then it may make sense to use the weir equation over the 2D equation. Are you using the diffusion wave or the full momentum solver?
cameronParticipantif you right click on the .prj file, go to properties, select change (opens with), and go to the HEC-RAS executable.
This should not be required though as HEC-RAS 5.0.1 can read 4.1 files just fine.
July 13, 2016 at 6:22 pm in reply to: Overlapping cross-sections although downstream reach length not zero #9994cameronParticipantHow were the cross-sections created? Did you use GeoRAS? What was the horizontal projection of the model?
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