DC Fan RPM VS CFM

[electrosalt]

Folks, I contacted the vendor of a project I am working on to request which DC fan I should use. They told me that the fan I am looking for should be:

12 VDC
1000 RPM
6 CFM

However, I went to a dc fan search site:

https://www.mouser.com/Thermal-Management/Fans-Blowers/Fans/DC-Fans/_/N-dwatb/

And there is nothing that matches 1000rpm/6cfm and 12vdc. My question is, can I get a fan that has for example 6 CFM and 4000 RPM or does the fan have to be the same RPM as the specs that the vendor states. I am under the impression that the CFM number which is the flow per minute is the important number, and in this case a slow flow is what is important for the project. Please correct me if I am wrong. Thank you.

 

[ronsimpson]

I agree you want 6 CFM. How you get 6 is not important.
I think lower RPMs will cause less noise.
Probably a high RPM motor will have small blades. A low RPM motor will have many large blades.

 

[kubeek]

Do you have some preferred dimension? You could simply run a larger more powerful fan at lower RPM to get the required flow. However there will likely not be any easy way to realate % of max RPM to airflow, so it it will be more of a guesstimate.

 

[electrosalt]

Do you have some preferred dimension?

It should be 70mmx70mm. Thanks.

 

[schmitt trigger]

So you have your three important parameters: size, airflow and voltage.

You can go to Digikey's website and perform a filtered search.
You could find a situation where there are no 12 volt, 70X70 mm fans that have exactly 6 CFM. In that case, widen that parameter search, let's say from 6 to 9 CFM.

As others have mentioned, lower RPM usually results in lower noise, which may be important in certain applications.

 

[electrosalt]

Thanks! I think this one ought to do it: NMB Technologies Corporation 2810KL-04W-B10-P00 its 70mm x 70mm x 25mm with 19CFM.