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Creating a pulsating water flow with a paddlewheel. 1

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aguenst

Mechanical
Jun 12, 2012
3
I am trying to make a prototype of a new kind of pulsating machine similar to the pulsations and water pressure seen in a Water Pick(Oral Irrigation) device. I am going to try to use a paddle-wheel mounted inside a water tight cylinder that barely circumscribes the paddle-wheel. The entering pipe will be positioned parallel to the exiting pipe and will be located near the edge of the paddle-wheel for the larger moment force. There will also be a one way air valve attached to the cylinder. Now I think the device will pulsate, but I don't know if it will because of temporary pressure change when the paddle-wheel blocks the exit or if it will because of air being sucked into the system. Anyone have any advice??
 
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I forgot to mention that this machine must run off just regular house water pressure, and no electrical source of energy is possible.
 
spinning, relatively large, paddle wheel is too complicated and precisiion intense. Try a wing section shaped flapper, lift generated by passing water pulls flapper slightly into water stream, opens an air entry port and the reduced pressure draws air in just as the flapper begins to restrict the water flow causing the flapper to close and seal the air inlet again. Something like that.

If it ain't broke, don't fix it. If it's not safe ... make it that way.
 
By precision intense do you mean the angle the water is hitting the wheel? The diameter of the wheel would be about 2.5 times as large as the inlet tubing. This is based off quarter or half inch tubing also.
 
fabricating tiny paddle wheels, then spinning them in tight quarters at high rpm and keeping the bearing surface from wearing down and the clearances tight isn't as easy as it looks. If you manage to do it economically, it probably won't run very long.

If it ain't broke, don't fix it. If it's not safe ... make it that way.
 
How about a miniature sprinkler head? Similar to the showerhead suggestion.
 
It sounds like a mini-horizontal centrifugal "pump" - something like a Goulds-ITT 3144 model ? - but you're removing energy instead of adding it.

But those don't "pulsate" when they add pressure to a system, why would expect the waterwheel to pulse? If the wheel is restricted (by a brake or by friction) wouldn't that be a wear point or fouled by deposits and scum/biologics buildup?
 
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