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cameronParticipant
You would probably have to check the HDF files for this and write a script to automate it. I don’t think there is a way in Mapper to tell you this.
cameronParticipantThis is a very generic error and cannot provide any real answer.
Does the model run without the breach?
cameronParticipantThere is a way to do this. HEC has a software called RTS (CWMS non-public version) that you can set up to grab data from a website, enter it into HEC-RAS, and map the floodplain.
cameronParticipantI believe it uses the interpolation surface TIN that gets created (under cross-sections in Mapper) and converts it to a raster using a sampling technique at the size you specify.
If you interpolate a lot of cross-sections, you have more control over what the terrain looks like as you can add breaklines to the the interpolated cross-sections so it will look better.
The interpolation surface is linearly interpolated between cross-sections, but you can control it a little bit with the edge line layer in Mapper.
It uses the location of the cross-sections to determine everything and I do not believe it uses reach lengths at all.
cameronParticipantThere isn’t really one place to look. If you want to see some examples people have done, you could look at conference proceedings as people have tested a lot of different things in HEC-RAS.
November 20, 2019 at 6:14 pm in reply to: Negative flow at the sluice gate/unknown water source at the gate #12628cameronParticipantfor your gate invert values, are they below the lowest elevation of the grid cells they are connected to?
cameronParticipantFor a dam break, I wouldn’t worry about it. The default is set to zero and the model ignores it. There is discussion about it in the manual and a range of values, but most people just ignore it when they use HEC-RAS.
In general you should always calibrate and validate your model and this could be a knob to turn to help calibrate.
cameronParticipantit will save out a *.tif file of the depth, water surface, and a few other options. It can also create polygon shapefiles of the inundation extent.
cameronParticipantI would go the manual route then. One option would be to use the crayfish plugin in QGIS to load in the mesh, then get the centroids, then load the centroids into HEC-RAS.
You could get a temporary license for SMS as well.
cameronParticipantAdding more cores does not always make an improvement as the program has to split the model up for each core. You would want to determine what is the optimal number of cores required. HEC-RAS also uses physical cores only so on the cloud/server you would need to make sure you are looking at physical cores not virtual cores.
You would also want to make sure you are using a cpu with a high speed as some of the larger chips with large amount of cpu’s have lower speeds.
There is some documentation on this as part of the 2D manual for HEC-RAS and on the blog as a post.
cameronParticipantif the *.2dm mesh is from SMS, there are tools to convert it to an HEC-RAS mesh in SMS. You would otherwise need to get the centroid of each mesh element and the mesh boundary and import manually in the “Edit/View Points” button.
cameronParticipantMapper only displays what the results show. If the results show they are underground, it will not display in Mapper. You would need to update your terrain to reflect channel data.
November 18, 2019 at 6:55 pm in reply to: Negative flow at the sluice gate/unknown water source at the gate #12626cameronParticipantDid you try turning on flap gates so there can be no negative flow?
cameronParticipantDoes the terrain reflect the data in the cross-sections? Does the water surface go below the terrain?
cameronParticipantDoes the water ever reach the low chord of the bridge? If not, you could model the piers as blocked obstructions and not worry about the skew of the bridge.
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