is there a formula to get the cfms after 7 volt trick

[lapdog]

is there a formula to get the cfms after 7 volt trick is preformed.

 

[techfuzz]

I'm not sure but this may work:

7/12 = 58.3%

58.3% x Original CFM = New CFM

I'm not a EE person so someone with a EE background please correct me if I'm wrong.

 

[Belegost]

Actually I don't think the conversion is nearly that simple. Fan blades are designed for the RPM they were made to run at, so underspinning them may lead to more dramatically reduced performance. I would suggest looking up the specs for your fan brand on the manufaturer's website, or calling them directly.

 

[MrHelpful]

If all else fails... CFM meter.