- #1

Mattsnooze

- 15

- 0

Hey. As the title dipicts, is there any relationship between CFM and PSI, linear or non-linear?

Any mathamatical relationship either?

CFM (cubic feet per minute) is a volume over time, and PSI (lbs per square inch) is a weight essentially over an area. So I take it, there's no real way to linearize it?

For instance, what's the compression ratio of a typical 12V compressor (high end)?

Also, if one compressor can produce 100 psi, and another 300 psi. Does the 300 psi unit have a higher compression ratio? I know the compression is usually pistons that very quickly pump in tinny volumes of air (30mm - 60+mm pistons) so I'm sure the size of the piston's determine how fast and how much max pressure they can compress (I think would be inversly perportional ( bigger pistons faster compression, but lower Max pressure?)would it not)?

Also, if a compressor and tank combo store let's say at 200PSI. If you tap a valve directly off the Tank, the second you open the valve air comes out at a Descending PSI rate would it not? So all that being said, the larger diameter the valve, the higher the CFM, but the lower the PSI? Or is PSI the same, but the tank just drains faster, and the PSI drops faster proportionatly?

(sorry for some of my spelling errors, I'm trying to type fast B4 I go to work)

I'm doing research on compressors and how the sizes of the chambers/ports/wheels all play a part in balancing CFM and PSI, depending on the application. So in order to work with them I would like to understand if there is any relationship between the two or not.

So from a design perspective I would like to learn how to design compressors for the variet of applications (from low cfm (high psi), to High CFM(high PSI) and the few combinations between.

I've read a crap load of formulas, and engineering documentation, so now I would like to understand/re cap with what I've learned and hopefully develop upon that.

The designing is for different methods of forced induction on automobiles. So even if you have automotive experience I would appreciate If you chimmed in. thanks in advance.

Any mathamatical relationship either?

CFM (cubic feet per minute) is a volume over time, and PSI (lbs per square inch) is a weight essentially over an area. So I take it, there's no real way to linearize it?

For instance, what's the compression ratio of a typical 12V compressor (high end)?

Also, if one compressor can produce 100 psi, and another 300 psi. Does the 300 psi unit have a higher compression ratio? I know the compression is usually pistons that very quickly pump in tinny volumes of air (30mm - 60+mm pistons) so I'm sure the size of the piston's determine how fast and how much max pressure they can compress (I think would be inversly perportional ( bigger pistons faster compression, but lower Max pressure?)would it not)?

Also, if a compressor and tank combo store let's say at 200PSI. If you tap a valve directly off the Tank, the second you open the valve air comes out at a Descending PSI rate would it not? So all that being said, the larger diameter the valve, the higher the CFM, but the lower the PSI? Or is PSI the same, but the tank just drains faster, and the PSI drops faster proportionatly?

(sorry for some of my spelling errors, I'm trying to type fast B4 I go to work)

I'm doing research on compressors and how the sizes of the chambers/ports/wheels all play a part in balancing CFM and PSI, depending on the application. So in order to work with them I would like to understand if there is any relationship between the two or not.

So from a design perspective I would like to learn how to design compressors for the variet of applications (from low cfm (high psi), to High CFM(high PSI) and the few combinations between.

I've read a crap load of formulas, and engineering documentation, so now I would like to understand/re cap with what I've learned and hopefully develop upon that.

The designing is for different methods of forced induction on automobiles. So even if you have automotive experience I would appreciate If you chimmed in. thanks in advance.

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