2D mesh geometry import issue for large meshes

0 votes
asked Apr 20, 2017 by m.weber (120 points)

I've been successfully using RiverGIS for mesh creation, but if a mesh includes too many cells the HEC-RAS Geometry import fails. I'm not sure where the threshold is, but it definitely does not work at around 250,000 cells. This is a problem for me, as I often work with large 2D models. 

What happens is that the cells that were created along the breaklines are absent. Here's an example screenshot where the regular grid imported, but the curvilinear portion within the channel fails. 

Anyone else notice this issue? What is going on here?

FYI, I cross-posted this issue to github: https://github.com/erpas/rgis/issues/28 


commented Apr 20, 2017 by rpasiok (2,241 points)
Hi Matt,

Thanks for your report. We didn't get into such problems. Would you like to share your dataset? That would help us reproduce the problem and look into it if we had the following layers:

1. FlowAreas2D
2. BreakLines2D
3. BreakPoints2D (if any)
4. DTM (optional)

1 Answer

0 votes
answered Apr 23, 2017 by rpasiok (2,241 points)
Hi Matt,

The size of your model might not be relevant here. The problem is that your breakline endpoints are located outside of the 2d flow area. Modify your breakline to start and end inside of the 2d area - it should not cross the 2d area boundary. Hope that helps.
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