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siphon water uphill

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elizasue1

Agricultural
May 5, 2002
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I am starting a feasibility study for a client that wants to move pond water uphill by siphon. The system would be primed with a small jet pump at the lowest pond (pipe inlet elevation 92.00). The stand (riser) pipes will be limited to 20ft lift (site restrictions). My initial research concening Bernoulli's equation shows a max lift of clean water of 10 meters (~32.8 ft). How do I determine density of fish pond water and what affects will the impurities have on my ability to keep a siphon at the crest. If my elevation difference between pond water surface levels is a max of 35 ft, what is the best way to determine the number of stand (riser) pipes needed to move the water uphill by siphon only? Seems like it should be feasible. Just need a place to start. See attachment for clarification.
 
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The material and riser pipe heights shown on the attachment are what the client has on site and wants to determine if the material and diameters will work for this system. The 20 ft riser limit is due to installation and site restrictions. The riser pipes can be lower, but just not higher than 20 ft.
 
If memory serves - siphons will not move water up a hill. The exhaust has be lower than the inlet.

There is an old mechanical type pump that can allow you to do this. Don't remember the name or how it works.
 
There is a type of ram-jet pump (or some variation of that name) used by the Amish to convert the energy in flowing water to a pumping action that pushes water uphill. Essentially a chamber with a series of weighted and timed check valves to create a pulse. Do a google search.
 
Found a quick explanation -

Hydraulic ram pumps
A hydraulic ram is a water pump powered by hydropower.

It functions as a hydraulic transformer that takes in water at one "hydraulic head" (pressure) and flow-rate, and outputs water at a higher hydraulic-head and lower flow-rate. The device uses the water hammer effect to develop pressure that allows a portion of the input water that powers the pump to be lifted to a point higher than where the water originally started.

The hydraulic ram is sometimes used in remote areas, where there is both a source of low-head hydropower, and a need for pumping water to a destination higher in elevation than the source. In this situation, the ram is often useful, since it requires no outside source of power other than the kinetic energy of flowing water.
 
You should consider draining pond 2 through a small hydroelectric generator into pond 1.

You need somewhere around 1.5 HP for each 100 gpm you lift by 35 ft. Even more with small diameter pipe.

Only put off until tomorrow what you are willing to die having left undone. - Pablo Picasso
 
MiketheEngineer has it right. For a siphon to work, the outlet should be lower than inlet. So in principle, your sketch doesn't work.

I'd be glad to see your Bernoulli calculations, but I guess that the 10 meter you mentioned, comes from the 1 bar atmospheric pressure converted mistakenly by you in one side of the Bernoulli equation.
10 meter is the maximum theoretical height that water can go up provided that the outlet of the pipe is lower than the inlet by a minimum static height that could compensate the pipe friction losses. The friction depends on flow, so the more flow needed, the lower the outlet should be (comparing to the inlet). You can take a plastic tube and experiment it yourself. Do you think by putting one side of the tube in a pool, water comes upward in the tube if the other side is located in a higher level?!

Water never goes uphill unless you add energy to it. ram pumps, air lifts, etc, are along this line.

And nothing is for free. Perpetual machine has fascinated human mind over centuries. Your prefeasibility study is not the last one. However, as mentioned by BigInch, there is a possibility of transferring water from pond 2 to pond 1. Implementing Bernoulli, the positive static head could flow the water toward pond 1.
 
In Colorado we would make the cows walk to the other pond. However I would guess that you could do it with a windmill. Assuming that the amount of water you want to move is not that great. The 6" pipe scares me off a little bit but I don't know if you are using it for pressure drop or you are thinking you are transfering 1000 gpm?

Regards
StoneCold
 
You need a "green" pump; most green processes do not have to follow thermodynamic ,or other laws.
On the other hand , I do have 2 Koi ponds with 10' elevation difference and a 50' "river" between them .However, I use a plain old electric pump to return the water.
 
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