Dears,
We have a project area that is part of a bigger drainage catchment where the remainder of the area is upstream of our subcatchment. We built a model using GIS information of exisitng network (invert levels and pipe sizes ) for only the portion of the network within the project area. For this area we have done calculations for a weighted C and a will be using rational method catchments and linking them to catch basins in the model.
For the upstream area we will consider the whole area at once, its drianage path and resulting Tc and IDF curve corresponding intensity (becuase of a different adjusted IDF than the one in our area that is driven by dominant landuse as per local regulation) and we will calculate a fixed inflow that we will be added to the manhole at the point where the upstream catchment connect to the network passing through our project area (this is for planning purposes not engineering design). While in analysis mode, we get all kinds of warnings with regards to min/max velocity and slope not met as well as flooded nodes.
The main thing is that once the model is run, in the calculation summary, we get the "Convergance was NOT achieved" warning. So before using the results for reporting we want to know if the convergance warning implies the results are not reliable or what are the implications of this type of warning.... one is more used to the green light once in design mode!
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Regards,
Jesse DringoliTechnical Support Manager, OpenFlowsBentley Communities Site AdministratorBentley Systems, Inc.
Thanks Scott, yes, the flooding is an indication that the system is undersized and it is something we will report on. The notifications on IL of conduits being lower than the nodes they connect to is due to the way we extracted the IL of each catch basin from the links database using a look up function in excel but without seeking the lowest IL-in/IL out of the pipe connecting to the catch basin . It was perceived the analysis results wont be sensitive to it since each conduit is well defined with a start and stop IL (what do you think?). We did increase the max network traversals to 50 in the same model we sent you and convergence was achieved.