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When displaying EGL lines in the long section view, EGL is frequently shown to increase across manholes in the downstream direction (and direction of flow). This should not occur as (excluding pumps) if energy was really is higher on the downstream side the flow would be upstream?
The problem is most acute when using the 'max' button, presumably due to the velocity head being calculated using a very high velocity caused by instabilities. However it frequently appears in long sections taken at a particular time step too.
This issue has caused some engineers that I work with to lose confidence in ICM outputs and ICM in general. The work around it to just not show the EGL but that isn't ideal as EGL is useful to display.
Thank you for raising this, would you please contact our support team so they investigate the model and interpret what is happening. The CS team can escalate cases to the development team for further investigation or if they conclude that there is a potential issue with the how EGL is being plotted on the long seciton view.
I will move this to "Already Exist" assuming that you'll contact our support team and so we don't have it on multiple records.
InfoWorks ICM solves for mass and momentum (not energy) using the Saint-Venant equations. The EGL shown in the model is primarily for reference and visualization, not a direct output of an energy equation solution. It helps users interpret results in the context of traditional hydraulic analysis but should not be viewed as a rigorously computed energy profile