Simple Air Permeation Experiment
Simple Air Permeation Experiment
(OP)
I am working on an air permeation experiment to show the difference in air permeation between three fabrics. If you use lab testing equipment, you get air perm values of 221 CFM, 86.6 CFM, and 35.6 CFM respectively. I tried a set-up with a ping pong ball in a clear tube and a fan blowing up on it across the fabric, hoping that you would be able to see a difference in height, but it wouldn't work. The fan wouldn't even blow confetti around when the fabric barrier was in place. Does anyone have any ideas why this is not working?





RE: Simple Air Permeation Experiment
Shop vac (vacuum side) pulling from top of the tube may work.
RE: Simple Air Permeation Experiment
As noted - you really need a wind tunnel or equal.
RE: Simple Air Permeation Experiment
RE: Simple Air Permeation Experiment
B.E.
The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor
RE: Simple Air Permeation Experiment
RE: Simple Air Permeation Experiment
You need something that can either:
Establish a fixed and known pressure drop across the sample, then measure cfm.
or
Establish a fixed and know flow through the apparatus, then measure the pressure drop across the sample.
RE: Simple Air Permeation Experiment
RE: Simple Air Permeation Experiment
RE: Simple Air Permeation Experiment
Then we conclude that your company doesn't know what it's doing and don't ever buy anything.
You want people to come to your booth, hire some pretty girls.
RE: Simple Air Permeation Experiment
They should save the salary money and figure out a test that demonstrates what they're trying to show.
Even if you get the blower installed the right way, what is the blowing confetti or ping pong ball going to prove? If the fabric permeability only works under certain conditions, then how is the OP's company going to ensure that in actual applications customers are getting the permeability they want?
Patricia Lougheed
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