I am trying to run a automated fire flow scenario, however I would like the flex table to stop calculating or display once 3500 gpm is reached or 20 psi residual. I have set up the following (see image) but my flex tables will not calculate up to 3500 gpm when the residual is not 20 psi?
Hello,
It means that there is a node where the zone pressure reaches 0 psi. Additional fire flow will continue to be added to the system until the fire flow upper limit is reached or either of the two pressure constraints (residual or zone) is reached. In this case, it appears that the zone pressure constraint is reached before the fire flow upper limit is reached.
Typically there is a column in the Fire Flow Node Table called "Junction w/ Minimum Pressure (Zone)". This will display the junction with where the lowest pressure in the zone is located.
Information on understanding the fire flow results and how they are derived is found in this link, which Jesse provided earlier.
Regards,
Scott
I did notice that the pressure (calculated zone lower pressure) was 0 psi for those runs that did not continue to 3500 gpm or 20 psi? what does that mean?
I looked at the fireflow status and it says passed for all the nodes.
If you only have one pressure zone, that means that if the pressure falls below zero at any node in the network during an individual fireflow run, it will stop. The network unbalanced would not show as an error / notification because it would occur during an individual fireflow event. You will need to look at the "Fire flow status" column in the fireflow Flextable along with the other fields to determine why the fireflow stopped short.
See:
Jesse DringoliTechnical Support Manager, OpenFlowsBentley Communities Site AdministratorBentley Systems, Inc.
i only have one pressure zone in my system. i am also not getting a network becomes unbalanced error?