knowing the use of the apparatus is crucial, the higher cfm in a small tube will generate all kind of problems, for example whistling, vibrations, etc. Some king of air pressure equalizer could be used. the greater the diameter of the tube, the better air flow efficiency with no wind noises. In my aquarium, i had a bubble bar that supplied evenly bubbles over the lenght of the bar. the tubing was 1/8 and the air pump was accordingly. You could pay a visit to your best petshop and could try out things. One thing i would not overlook is the quality of the air in and out of the apparatus, filters might be essentials. You could also check your scuba diving shop. Also check www.tankfill.com, www.yachtdiver.com, one time i used my scuba tank for filling a small zodiac we knew it would get cold at the end piece, but not that cold ... that might be the way to go, it would rest your mechanical pump.

Tubing is used to transport fluid and gas in pneumatic, hydraulic, or process applications. Tubing differs from pipe in that tubing's outside diameter or size is controlled and used for product designation.

This leaves an inside diameter of apprximately 1/8" and each hole will decrease the pressure > 1/2 which is repeated 20 times leaving very negligable pressure at the last hole.

One would need a seperate compressor for each hole or a manifold large enough to supply air at negligable pressure drop to each hole.

200 psig = 13.6 atm.

3891 scfm = 286 cfm at 200 psig

286 cfm = 4.766 cf/sec

.25 in tube has crossectional area of .0013654 sq-ft

velocity the air has to reach to travel down the mouth of the tube = 4.766/.0013654

= 3490 ft/sec = .66098 miles/sec = 2380 mph

density of air at 200 psig is roughly 1 lb/cubic feet.

velocity pressure of 200 psi air at 2380 mph = 1/2 ρ v² = 1/2 * 1 * (3490)²/32.2 = 1313 psi

So if the air pressure to the tube was 1500 psi, you could have 200 psi air in the throat of the pipe with the necessary velocity to deliver 3891 scfm. However as you have supersonic flow, other problems arise that would probably prevent this velocity in the restriction of the pipe.

"I would like to supply 200 psig to a 20 foot long, 1/4" tube (We will take that to be .25 I.D.) that has 1/8" holes every 3 inches".

Obviously, in reality, the question is "How do I supply 200 psig air to 80 1/8" nozzles space every 3" along a 20 ft long header.

And the answer is get a GREAT BIG AIR COMPRESSOR !

If that is the question simply hook the line directly to the compressor. The size of the compressor will depend on how many high speed tools are used on the line.

Increase the spacing.

I don't think it was posted in jest. Someone's trying to make some type of air curtain. the 3891 scfm is absurd but this problem could be modeled. Yes, it would take a large compressor. Obviously, there would be severe pressure drop as you travel down the tube. If they really wanted an air curtain, this tube should have had reducing sections to equalize friction, thereby ensure somewhat equal discharge velocities.

I believe it would have more merit if there were only 10 psi.