Hi.

I am looking for air flow meters that can measure l/s of air flowing through a utility tunnel. The meters will not be installed in any ducts - they will measure the flow through a cross section 3meter by 1.5 meters. Expected velocities in the tunnel are - minimum 0.3 meter/sec to a nominal of 0.8 meter per second.

Can anyone suggest a suitable air flow meter for this application?
Thanks you!

 

You might look into a handheld anemometer, some are available for very low velocities. Omega Engineering has # HHF144B: 0.2 to 40.00 MPS (40 to 7800 FPM) that might work for you.

John Catch
[email protected]
www.inflowinc.com

 

If you get a cooling fan something like you would install in a large cabinet. An AC powered type not DC you will find it puts out a fairly nice low Voltage sign wave.

Wire this into a Frequency to current converter and you have an inexpensive turbine meter.

If you need to calibrate it strap it on top of your vehicle and drive down the road at different speeds.

I have used this with great success in low pressure ducts

Hope this helps

 

I thought I was alone in this out of the box thinking.
I find it sometimes helps to run a few ma. of DC current through the fan for consistent magnetization.

Regards
cww

 

Reading your post again in the light of day.
The Velocity is very low but a fan might still work.

A thermal flow transmitter perhaps?