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CFM OUTPUT IN SERIES FANS
- Thread starter Bear Claw
- Start date
Both fans theoretically will operate at the same CFM. So if you have correctly determined/calculated the pressure of your system, and the sum of the pressure from your two fans equals that (at the 5,000 CFM you want), then they will both operate at the 5,000 CFM you want.
It can be more complicated than that if you are looking at part load (if your system has that) or if you are selecting two fans at 5,000 CFM but at different pressures. This link may be helpful
It can be more complicated than that if you are looking at part load (if your system has that) or if you are selecting two fans at 5,000 CFM but at different pressures. This link may be helpful
LittleInch
Petroleum
Bear claw - No one knows as you haven't given any real technical detail.
All you can say as others above have done is that the mass flow through both fans will be the same assuming there is no leakage inbetween.
It is highly unlikely that the flow will be 10,000 cfm as then both fans would be operating at 200% of their nominal flow. It all depends on the shape of your fan curve for flow vs pressure and what is downstream of the second fan. If you read your referenced post properly you'll see what I mean.
It would help if you could explain what your issue is and what you are trying to do with two fans in series. It's usually much better to have a single fan sized correctly for the required pressure and flow for your particular system.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
All you can say as others above have done is that the mass flow through both fans will be the same assuming there is no leakage inbetween.
It is highly unlikely that the flow will be 10,000 cfm as then both fans would be operating at 200% of their nominal flow. It all depends on the shape of your fan curve for flow vs pressure and what is downstream of the second fan. If you read your referenced post properly you'll see what I mean.
It would help if you could explain what your issue is and what you are trying to do with two fans in series. It's usually much better to have a single fan sized correctly for the required pressure and flow for your particular system.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
Total flow is not the sum but the same. It is the total pressure of the fans that is additive. You have to calculate the total pressure through the system at different CFMs then compare with the fan system cure to come up with the situation meeting the above requirement. You can refine your next trial CFM by interpolation.
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