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cameronParticipant
Have you tried deleting all the hdf file and rerunning? Also make sure you are using the latest version of HEC-RAS.
cameronParticipantall output can be found in the hdf file if you want to create a raster from that. In Mapper if you right click on the results label, select the render option and it will give you a chance to change it hybrid (default) to Horizontal (which is what it really computes).
cameronParticipantare you using the latest version (5.0.3)?
cameronParticipantAre you using commas as decimals?
January 9, 2017 at 7:06 am in reply to: Channel n values in Manning’s n Table (light green background) #10321cameronParticipantWhat happens if you tell it to use just left, channel, and right n values (does it work)? Did you check the composting n value to verify it was working (define in a table)? What happens if you filter some of the points out?
I don’t think it matters that those areas are not in green, but check the things above as it might bring peace of mind.
cameronParticipantWhat time step did you use for the simulation?
January 9, 2017 at 2:04 am in reply to: Can I perform 2D-Steady Flow Modeling using HEC-RAS 5.0.3? #10328cameronParticipantIf you ran a constant hydrograph long enough, it would be considered steady state.
January 5, 2017 at 7:13 pm in reply to: Channel n values in Manning’s n Table (light green background) #10319cameronParticipanthow did you define your bank stations? You don’t need to have changes in n values at bank stations, but usually the n values that are inside your banks does appear green to help visualize what n values it will use. HEC-RAS will create one n value for inside banks while it is running and there are options to adjust how it does this.
January 5, 2017 at 7:00 pm in reply to: Dam Breach Model using 2D in HEC-RAS 5.0.3: 1D/2D Flow Error Message #10318cameronParticipantThis message is stating that there is an error of that much flow across your 1D/2D connection. To fix this, you either need to adjust the connection or increase the 1D/2D iterations to 20 if not done so already.
cameronParticipantWhat I would recommend is to place cross-sections at the beginning and ending of the art piece which include the blocked obstructions and then place cross-sections 1 ft away upstream and downstream that do not include blocked obstructions, but you would need to include ineffective areas.
cameronParticipantThis blog has an answer for you
cameronParticipantIf you are trying to create a surface from the modified XS in HEC-RAS, you can inside of Mapper. You can either create the surface based on the entire cross-section or just based on what is between the banks.
December 29, 2016 at 7:46 am in reply to: Advanced rules to control gates in internal SA Connections (2D Mesh) #10292cameronParticipantI tested this in a study I am working on and found that the advanced rules do not apply either. I would assume it should work, but this is something that should be brought up with the developers.
cameronParticipantI usually set up the model in GIS and snap everything together. If you already have a model, you can export out the layers to GIS and adjust them before bringing them back into HEC-RAS. If you are zooming in close like you say, that should get rid of the gaps as well if done right.
cameronParticipantthe the cross-sections, lateral structure, and 2D model boundary overlay exactly on top of each other? It does not appear that it does based on the image you provided. HEC-RAS creates a interpolation layer (see RAS Mapper) that it uses to generate the 1D results which if does not touch a 2D area means there will be a gap. The only way to fix this is make sure the layers are right on top of each other. In some cases you will need to add more cross-sections to get it to match up if the river meanders between cross-sections.
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