How do I measure CFM of a fan?

unibomber51 · Post by **unibomber51** » Tue Oct 03, 2006 1:01 pm

jaganath · Post by **jaganath** » Tue Oct 03, 2006 1:08 pm

Tricky without expensive measuring equipment. The DIY method is to have a heat source and measure its temperature when exposed to the CFM from the fan, this will tell you relative CFM.

Or you could buy a hot-wire anemometer.

einsteingodel · Post by **einsteingodel** » Tue Oct 03, 2006 3:08 pm

You need a device called an anemometer. There are many varieties, but for our purposes, the simple type designed to measure a single component of the air flow vector is called for. These run from about US $100 to ten times as much and more. Unless you have a constant need to measure airflow sources, the DIY method that jaganath refers to would be much more practical and involves just basic math,

Or, provided you do not stray from recommended fans, you can take the word of reliable sources...

http://www.silentpcreview.com/article63-page2.html

I might be wrong, but I cannot phantom the sample variance from fan to fan of the same model to be much of an issue.