I checked SewerGEMS help and found Bentley SWMM is using HEC-22 equation to calculate the inlet efficiency, is that correct?
upon reviewing the efficiency calculated by the model for example (CB-433) in the shared model with scenario "5 Year 45 minutes" and perform the hand calculation as in the shared excel sheet; I would clarify the followings;
1- does SewerGEMS calculate the inlet efficiency as per HEC-22 shown in the help?
2- why the hand calculation does not match with the model results as shown in the shared excel? can you provide an excel modified in case there is a mistake in my excel for verification?
3- would you please elaborate why the graph in the efficiency does not back to 100%, it ended to the end of simulation at 40% ? while the excel shows the graph back to 100?
PS: in the same shared model; when I do zoom extend the model does not extend and I zoom little out I saw many dash lines, I did compact Database and Update Database Cache but still the problem there (Screenshot is below).
The model and the excel are shared in Bentley Share Drive
Regards,
Mohamad Azzam
Hello Mohamad,
We are looking into this and will get in touch with you soon.
Scott
This appears to be related to a similar issue that you reported earlier. It looks like modeling noise is having an impact on the capture efficiency. I will make sure the development team are aware that this issue is continuing.
Dear Scott
That modeling noise belongs to point 3, in that post was to InSag, but this is On Grade. we need to present the graphs to the client. any workaround/advice or patch.
what about the other points? the HEC-22 and the calculation comparison between the excel and the model.
Also the display (Zoom extend issue).
Kindly advise.
Thank you,
Mohamad
The display issue can be resolved by closing the model, browsing to where the model is saved, and deleting the .stsw.dwh and .stsw.dwh.01.bak files. When you open the file again, new versions of the DWH file will be created and the display issue should be resolved.
For the other issues, I am checking with some colleagues and will get back to you.
Hello Scott,
I downsized the model for simplify the investigation, also I applied Ponded Area for all inlets (1 m2) and also for all manholes (500 m2), then I did manual check for the inlet (CB-387), but still getting similar output in terms no matching model with excel calculation and the efficiency graph is back to 40% last part of simulation.
The simplified model and the excel for that particular inlet are shared.