What is the formula for converting CFM pressures

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tafeteacher
Posts: 46
Joined: Wed Dec 23, 2015 6:49 pm

What is the formula for converting CFM pressures

Post by tafeteacher »

Hi guys
I'm chasing the formula for converting flow at one pressure to another.

For example, let's say I have 100CFM@10" and I want to display it as flow@28". Does anyone know the conversion formula?

Thanks in advance
86rocco
Posts: 292
Joined: Thu Mar 04, 2010 9:01 pm

Re: What is the formula for converting CFM pressures

Post by 86rocco »

Flow is proportional to the square root of the pressure difference so to convert from 10" to 28" you would multiply by √(28/10)=1.673. However, this is a best case scenario, bear in mind that different pressures mean different air speeds and higher speeds can sometimes induce turbulence which can effect flow so the conversion from one pressure to another is not always so straight forward.
tafeteacher
Posts: 46
Joined: Wed Dec 23, 2015 6:49 pm

Re: What is the formula for converting CFM pressures

Post by tafeteacher »

Thanks for that. Exactly what I was after!!
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