how to calculate CFM if V changed?

[shankar]

Is there any wat to recalculate de air flow of a fan if i change the voltage?
lets say i have this fan for example :
Specifications:
* Fan Size: 80x80x25 mm
* Rated Voltage: 12 V
* Rated Current: 0.20 A
* Rated Input: 2.40W
* Power Speed: 2900 RPM
* Air Flow: 39 CFM
* Noise: 34 dBA
* Weight: 62 gm

I want to plug it to 7V to reduce noise, how do i calculate the CFM?

[DaveW]

Hmm...to be honest, i'd guess.

My money's on 22.75 being your new airflow. It should be fairly obvious how i worked that out.

-Dave

[shankar]

thanks for your reply
yes, i thought that too, 7*39/12, but thats only if its linear, can anyone confirm this?