So I found the following equation from ACGIH: Principle of Ventilation
Fan Total Pressure=TP(outlet)-TP(inlet)=SP(outlet)+VP(outlet)-SP(inlet)-VP(inlet)
Fan Static Pressure=FTP-VP(inlet)=SP(outlet)-SP(inlet)-VP(inlet)
The fan I am using is a centrifugal fan that exhaust directly outside the...
I am a little bit confused on this: After pressure balance by design, how could there be a critical path (since all paths have the same pressure loss now)? I am designing a local exhaust system and each path starts from the terminal to the exhaust fan.
To select a fan with the right static pressure, should I just use the pressure loss of the critical path or add up pressure losses from all the duct sections?
I am trying to locate the operating point for a multi-branch system. For the system curve, should I use a composite curve from all the branches or should I just use the critical path? Thanks!
Is pressure balance at duct work junction required only for equal friction method? I used equal velocity method to size my duct, do I need to balance pressure at junctions?
