Fans in Series 4

[Zeroman]

Please confirm that this is incorrect. If you place a 1200 cfm fan in series with a 1200 cfm fan you get the combined 2400 cfm. Company X says that this is a choice that I have, but I disagree.

Thanks Credible Sources.

 

[mt31]

I do not beleive that 2 fans in series will give 24oo cfm through a duct system. I think it is just like using 2 8" ducts to provide the same airflow as a 16" duct, it doesn't work.

 

[quark]

When you put two fans in series the capacity becomes 1200 cfm only. If you put them in parallel then the capacity can be 2400 cfm maximum.

 

[ChasBean1]

Someone's applying Kirchoff's Laws to fans in the wrong way. Batteries in series should double the voltage; fans in series should roughly double the static pressure (not the flow). I don't think fans will follow Kirchoff's Laws exactly but will approximate them (voltage being pressure and current being flow). I agree with you and think your advisor might need to remediate. I think you would get some increase in flow due to lower static pressures across each fan, but not a proportional amount (i.e., a 25-50% increase, variable based on fan curves, fan type, and the system in which they are installed).

 

[Zeroman]

Thanks Chasbean1, quark and mt31. Your responses give me 100% confidence.