Author Topic: Venturi Design  (Read 5805 times)

Offline Will_D

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Venturi Design
« on: June 16, 2017, 11:18:51 AM »
Any one have a design for a water jet Venturi?

The idea is a sort of pressure washer but without electricity!

I have access to our irrigation system. It is driven by a large pump and delivers about 6 bar and delivers through a 50 mm pipe network.

My idea is to make a venturi nozzle that will accelerate the water to get a high velocity effect as opposed to just using a crappy spray head.

I am aware that locomotive steam/water injectors use various curves in the design of the nozzles and restrictors etc.

Why do I want this? Its to power wash the mowers and other equipment in the club.
Engineer and Chemist to the NHC.ie
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Offline vtsteam

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Re: Venturi Design
« Reply #1 on: June 16, 2017, 10:32:17 PM »
Boy, it's been a long time since I read it, but there was a high pressure super water nozzle design somewhere it the Guy Lautard Machinist Bedside Reader series -- if I remember correctly it was a series of drilled concentric holes, not a typical smooth curve profile (as in a steam injector). Don't have them at hand at present, but maybe someone else does....?
I love it when a Plan B comes together!
Steve
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Offline vtsteam

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Re: Venturi Design
« Reply #2 on: June 16, 2017, 10:55:36 PM »
"Haralson Hose End", The Machinist's Second Bedside Reader.
I love it when a Plan B comes together!
Steve
https://www.youtube.com/watch?v=4sDubB0-REg

Offline naffsharpe (Nathan)

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Re: Venturi Design
« Reply #3 on: September 12, 2017, 03:30:43 PM »
I recall that you gain pressure but at much lower flow? Therefore at HP/Low flow you can cut the muck off over a longer operator's time but at LP/higher flow you have a lower operator's time to achieve the same end result. Higher pressures need to be combined with higher flows to achieve your objective. Volume at moderate pressures (about 3 to 4 bar) should be your aim not volume at high pressures, the cost would be enormous and the losses unjustifiable. In practical terms HP/Low flow will give a needle jet (small area) and LP/High flow will give a wider jet (greater area) , the first will strip paint, the second will clear the muck. Nathan.