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Anonymous Poster #1

Water Jet Through Air Gap

07/03/2012 4:00 AM

Hi,

Could you tell me, is the jet flow from nozzle-1 can be passed again into another nozzle-2 as inlet, to do work in terms of pressing spring provided at the end of nozzle line-2?. In between there is a Air gap. Could you tell me the effect of the discontinuity in the pipe system. A similar picture is shown below
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PWSlack
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#1

Re: water jet through air gap

07/03/2012 4:05 AM

There will be losses at the air gap, as the jet of water breaks up into a spray.

To minimise the losses, eliminate the air gap.

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jesw55
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#2

Re: water jet through air gap

07/03/2012 4:05 AM

Hi,

Don't know for sure but it seems highly unlikely to me.

What is the pipe diameter? the nozzle diameter? the air gap? water pressure? spring pressure you are trying to compress? length of pipes?

Best regards,

John

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user-deleted-1105
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#3

Re: water jet through air gap

07/03/2012 6:56 AM

Air gasps are common to meet water regulations in eductors (venturi devices) to avoid back flow. The flow from the nozzle usually flows into a much larger hole like a small funnel. Trying to get it to flow into a small hole blocked off by a spring is (i'd have thought) a pretty hopeless task. Move the spring further down line where the flow will be confined and may have some momentum. Or better still put your spring before nozzle 1.
As a quick test, sit at your desk and lob screwed up paper balls into your bin. Now try it with a book over the top of the bin QED!
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(I'll play with the ones on the floor later)

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phoenix911
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#4

Re: Water Jet Through Air Gap

07/03/2012 9:51 AM

Are you just using water, or is ther abrasives envolved.

Wear on the mixing tube can creat problems focusing the jet.

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Bill H.
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#5

Re: Water Jet Through Air Gap

07/03/2012 5:05 PM

Look here:

http://en.wikipedia.org/wiki/Injector

I can tell you if there is significant pressure, it won't work long!

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sawmilleng
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#6

Re: Water Jet Through Air Gap

07/04/2012 1:52 AM

This is off the wall enough to qualify for a homework assignment question!!

Anyway, it is an interesting one.

Presumably, some energy is moving from one nozzle into the other in the form of velocity pressure. Further, if you put a pressure guage on line-2, with the end of the pipe closed, there would be some pressure shown, coming from the energy in the water trying to enter nozzle-2.

Therefore, if there is pressure, it will be able to do work by pushing on a spring in nozzle line-2.

The effect of the discontinuity in the pipe system.....well, it will vastly drop the pressure from the pipe leading to nozzle-1 to the pressure recorded in the pipe coming from nozzle-2. It will also vastly drop the flow rate from pipe-1 to pipe-2. The actual flow characteristics of each nozzle will likely govern how you would see the pressure VS flow curve of the total system (pressure and flow in-1 compared to pressure and flow out-2. There is probably some equivalent circuit that could model this with combinations of flow and pressure controls, but you are probably detecting a bit of rust starting to flow along with my explanations!!

Don't ask for formulas!!! But I'm sure they could be figured out.

Jon.
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user-deleted-1105
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#7
In reply to #6

Re: Water Jet Through Air Gap

07/04/2012 3:27 AM

The equivalent electrical circuit isn't working at the moment because there's a break in one of the wires
Del

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jesw55
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#8

Re: Water Jet Through Air Gap

07/04/2012 3:34 AM

Hello Anonymous Poster#1, is anyone there? how about a response of some kind.

John

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user-deleted-1105
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#9
In reply to #8

Re: Water Jet Through Air Gap

07/04/2012 4:13 AM

He doesn't remember who he is
Del

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Bazzer Englander
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#11
In reply to #8

Re: Water Jet Through Air Gap

07/05/2012 4:44 AM

I can add to your "best advice" Never waste an erection even if your by yourself.

Bazzer.

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Bazzer Englander
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#10

Re: Water Jet Through Air Gap

07/04/2012 5:13 AM

Why????

Bazzer.

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ci139
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#12

Re: Water Jet Through Air Gap

07/05/2012 10:09 AM

if you examine your bath tap you notice that low pressure stream accelerates and gets narrower at lowwer elevation

you have decceleration and expansion unless . . . F;T . . . you redesign your nozzle 1 . . . i gess something like this

¯_____________________________________

-<CC>- (( (( (( flow ??? Hypersonic (( (( ((

_¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

// -- CC -- central cone before (extending some out of) the outlet
// -- like the supersonic jet intake

/!\ -- i don't really remember these technologies

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