How can I measure air flow volume through a small tube?

Question

Is there a device that will measure air flow through a small tube?

Answer 1

Yes, they are called flow meters.  Here is a good site about how flow meters work:

http://www.omega.com/techref/flowmetertu...

Answer 2

Here is the most simple way to do it:

Fill the tube with water,inject the air, measure the volume of water being push out within a certain time. This equivalent to the same amount of air..