pump and siphon

[TorchLitHill]

Working on a micro hydro operation, but am new to this, what I need to know is if there is a motorized pump out there that would, if power was shut off, be able to be used as a siphon , if the discharge point is lower than the feeding pool?

[maker of toys]

any centrifugal pump would do.  in fact, any NON-positive displacement pump should do the trick.

[Phil Timmons]

Interesting concept.

I guess you are sort of going "over" the dam rather than through the dam like typical "big Hydro" designs?

This seems like a vastly more simple dam concept than the typical hydro dam, I wonder how large one could build this?  

I guess the max power out as it is drawing a vacuum is limited by the height limits of a siphon?

[TorchLitHill]

How about this contemplation, while the pump will be discharging more water than what would be discharged by a simple siphon, once the pump is shut down will the flowrate stay somewhat higher from the power that it had or would it equal out to the flowrate of the siphons regular discharge rate?

[henjulfox]

I would guess it would go back to the regular siphon rate - minus the drag from the pump impeller.

-Henry

[TorchLitHill]

Yea, I was curious about the loss of flow from the obstruction of the impeller, but what would you think if before the suction line gets to the pump, it's divided into two lines with a Y, one that goes to the pump and the other bypasses the pump and joins up with the outflow line with another Y, what might the reaction be here?

Should I just forget the pump, and go with the siphon?

[henjulfox]

Aught to work as a normal siphon then. But...

If you don't use the "Y" then the loss from the impeller comes from spinning the

pump motor. Spinning a motor (generator) is the usual goal on this board. I don't

see how putting the generator at the usual location at the end of the line and

having the siphon push the water through would be different from having it at the

start of the line and having the siphon pull the water through. I've heard that

using an impeller type pump as a generator has been done with "limited" success.

A siphon is a pretty low flow rate. Unless you're using large lines I doubt you

would get much power. Could be fun to mess with though.

-Henry

[TorchLitHill]

Has anyone you know of used the power of eddys or of a whirlpool to produce power?, would be very interrested in that,

Although the end result of my project is to generate power, the main goal behind me doing it is more of a physics project, as in a Hydro Rue Goldberg contraption, instead of just useing one wheel, or jet, or whathaveyou, I'm trying to incorperate a self rotating archimedes pump, a jet, a whirlpool vortex, siphon, incorperating the old physics trick of a glass upsidedown in water,   keeping the water higher than the surrounding pool, on a larger scale of coarse, etc...

Although it probably sounds like I'm talking about some PM slash over unity type of device, it's not, just an interresting thought I got, and in the end I think it could have some interresting results, that I would be glad to share when I get it off paper and into my local stream.

[TorchLitHill]

Let me also say I'm serious about learning about hydro, just because this project isn't meant as a survivalist homestead type project, I think its going to be valuable tool to interrest others in the field, and I believe that the project I'm working on could have a neat attribute that could help designers of future hydro projects , micro and larger.

Time will tell I guess, but I've got to try it, for my own sense of curiousity and sanity.

[henjulfox]

Way over my head. Been too long since physics 101. Sounds like fun though and that's what it's all about.

Suggestion - I believe Mr Goldberg's devices always did something. Maybe throw a little generator in somewhere with a LED that lights up. Add some interest to the contraption.

-Henry

[maker of toys]

the two 'y's trick would work to eliminate pump-drag losses, with the caveat that you'd need some way to keep the pump's output (with the pump powered) from short-circuiting from output to input and really knocking back your flow. . . and severely limiting the pump's ability to start the syphon in the first place.  (which i'm assuming is the point of having the pump in the system?)

[TorchLitHill]

the bypass would have a shutoff, that I would turn a moment before turning off the pump.

Although this isn't related to the topic, I put a site up, thats geared towards fighting the new world order, if interrested in that kind of stuff, you can check it out at http://ebookvault.tripod.com/ but be warned, I don't like most of the republicans or democrats out there these days.

[TorchLitHill]

just thought I'd ad a couple of links on siphons

http://www.aquaticmanagement.com/siphdrain.htm

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