flow control valve actuator for fountain

Straight off the top - rather than linear fluidic actuators - you might consider a two or three on/off parallel array sprinkler valve set with flow restrictors, providing one / two / four flow rates which would provide eight linearly increasing flow rates on command. The price comparison ought to be favorable.

Brian W

Dear aaronlloydpeterson:

I don't think fuel injectors will take water, and window washer pumps are too slow.

Just not tolerant of water, and needs high pressure.

You pump will require positive flow to keep from overheating. I'd suggest a diaphrgam operated valve for each jet, that bleeds its flow back to the reservoir. Something like:

Use your controls to use air to pilot the valve closed. So a small air solenoid valve for each jet.

Then a small needle valve for each jet, so that each jet gets a good amount of flow.

pump -> manifold -> needle valve -> tee -> jet + | v pilot valve -> reservoir

David A. Smith

Brian Whatcott wrote in news: snipped-for-privacy@4ax.com:

That's probably a better bet. The only obvious candidate on a car is the heater mixer valve - which does not strike me as being likely to have the frequency response you'll need. Having said that I'm not even sure that modern climate control systems actually modulate the water flow, they may just use air blending.

Cheers

Greg Locock

I've been doing a bit more research on my backyard bellagio project. I'm considering a L type diverting valve and mounting my own actuators. The least expensive valve I've found is $25 on Grainger but I will continue my search.

valve has a mounting pad that I can use for a stepper motor bracket that I can machine myself. If this is a decent way to go I can mount a stepper motor and keep the cost below $60 per actuator/ valve/bracket. I'm going to check around at hardware stores for other inexpensive mixing valve options that might have flow characteristics smooth enough to correct in my software (I will probably be correcting the flow characteristics anyway to sync the valve with the midi values).

I am planning on using a charged manifold as suggested but using the diverting valves to send water back to the pump input. If I send the relief into the reservoir I'm worried about the turbulence disrupting the surface of the water too much. I figured this created an opportunity to create a pump supply side manifold with a large filter over its reservoir inlet. With all heads open there is no feedback and water is drawn through the large filter screen into the big supply manifold. With all heads closed, the pump would be supplied with 100% feedback. This is really just a large submerged quiet zone I guess. It could be constructed out of a 3' length of 10" diameter PVC and house the pump itself.

Recently found video of an MIT fountain project here:

I'm not going to make my heads dance just yet...variable flow only.

Please feel free to provide suggestions as I'm only a programmer. :-P

Dear aaronlloydpeterson:

Actuators will be hundreds of dollars for the "horizontal" 3-way valve you have selected.

This valve has a mounting pad that I can use

A stepper motor will not turn this valve. Not enough power. Turning torque is "foot pounds" when new. A gear box will blow your budget, and reduce operating times to a few seconds to turn on, and few seconds to turn off.

...

The pump adds heat, the flow controls will strip gasses out of the water. You feed that straight back into the pump suction, and you will destroy the pump. Put in a little waterfall, complete with "coral reef", and the returning water will get a chance to degas and cool, and the surface will not be disturbed too much beyond the "reef".

Davids A. Smith

I like the idea of a "charged manifold". A little 1000 gph pump only needs 160 watts, and isn't going to heat up the water.

I dislike the idea of using three way valves, especially with a stepper. Big enough steppers with drivers is going to be pricey.

I would run the pump full time, into the manifold, and use a backpressure regulator (relief valve) to maintain a flow, so the pump won't stall or cavitate.

For the valves, a dishwasher solenoid valve can be had for about $20. If you want variable flow, then add an air chamber at the outlet, and Pulse Width Modulate the solenoid. (Should be easy in software.) ;-)

Sounds like a bit of fun.

Dave

Yes, it will. Especially if plumbed in plastic, and short circuited back to the suction of the pump. Heat it up enough to outgass...

What about and "organ pipe" arrangement, with air blown in on the branch of a tee, air being triggered by a solenoid valve. The air would loft a short spurt, before it actually "sprayed", and would refill pretty quick from below.

It could simulate individual notes, just not sustained ones...

David A. Smith

I believe this is what they did on the MIT project.

Can you explain the air chamber to achieve variable flow? The one thing I've noticed watching these fountains in commercial installations is that they can create very calculated bursts of water; almost like perfect airborne 2 to 4 foot high columns. Could they be using a large needle valve? I guess I picture a 1 inch diameter needle valve without a threaded needle...like the actuator directly slides the needle in or out to control these rapid bursts...but can also create slow movements to control the flow. I fairly certain the valve/actuator is directly beneath the fountain head, too.

Hmmm.the mit student effort featured 3 ft tall thin jets? Four or five? They did oscillate, its true. And the light show was better than the water effects, in my mind.

The granger valve you show is comparatively expensive and manual. $25 ?? DO get a grip! :-)

eBay will sell you a double solenoid washing machine valve pair under 10 bucks. They are rated for at least 50 psi, so you might get a

40 foot high plume with the right nozzles.....

Brian W

Let's forget the grainger valve -- it was thread stimulation...which is somewhere between trolling and valuable contribution ;)