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cameronParticipant
for the run with the stage set, how does the stage compare to the normal depth boundary?
For the storage area run, does the flow leaving the 2D model match which is going into the storage area?
cameronParticipantWhat is the horizontal projection of the USGS data? The units are really small so it could be in degrees and not meters/feet.
November 28, 2017 at 9:20 am in reply to: Hec-Ras steady flow-Water elevation decreases as flow increases #11058cameronParticipantcan you supply the model for us to look at? What did you set for the inline weir coefficient and other weir parameters? What error/warning messages are you getting for the inline structure?
cameronParticipantIf you don’t include the storage area, is the model stable? How is the storage area connected to the model? If by lateral structure, what is the weir coefficient.
cameronParticipantThe wormhole culvert will transfer flow that far although the timing may not be 100 percent accurate.
You could do a 1D channel and flow from the 2D overbanks will go into the channel where it is connected. You just wouldn’t connect the culvert to the 2D area.
cameronParticipantHe is basically saying you need to use GeoRAS to calculate the reach lengths.
Since you say the survey data points you have are just for the channel and no overbanks, then the LOB and ROB should be the same as the channel.
It appears from your table that you have cross-section stationing for your cross-sections. If these are correct, then you could just copy the cross-section names into excel, subtract each row from each other to get a distance between cross-sections, and then paste it all into that table.
cameronParticipantYou can use Mapper and export out the floodplain of the floodway model as a shapefile and adjust as needed.
cameronParticipanthow different is the discharge upstream and downstream of the culverts? what does the hydrograph through culverts look like? Have you tested the culvert’s in another program to compare if they are working correctly?
cameronParticipantHave you tried a wormhole culvert?
cameronParticipantThis could be to your time step to high or it could be due to geometry issues like not having ineffective areas set correctly.
cameronParticipantare you using decimals or commas as separators?
November 16, 2017 at 5:55 am in reply to: Problem with connection 1D/2D: forrtl: severe (151): allocatable array is already allocated #11010cameronParticipantYou can not run a steady flow with a steady flow. You have to have a unsteady flow. This unsteady flow can be a constant flow and if run long enough, would act like a steady flow model.
cameronParticipantYou need at least 4 cross-sections that the user creates and HEC-RAS creates 2 internal ones which gives a total of 6. You can have more than 4 user cross-sections, you just need to make sure that ineffective flow areas are set correctly.
cameronParticipantYou could use a stream centerline as a breakline or banks as breaklines. It all depends on the river, how wide it is, and your cell size.
cameronParticipantWhat does the results show in Mapper? Why not export out the depths or water surface from Mapper? Then there is no need to use HEC-GeoRAS.
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