Running Water

Fla._Deadheader · August 15, 2009, 12:03:33 PM

Hope I get this 'splained right. :

:

There is a Spring on the farm next to us, that the runoff crosses our place. It is a gradual drainage, NOT very steep.

The ground is sandy Loam, with rocks that could fit in a pickup bed , only 2-3 rocks at a time. They are IN the ground, not laying on top. Where the drainage is, the weeds are 3-4 feet tall, falling over , and stretching for several feet. It's a vine type stuff only looks like grass.

Ground stays soft, except for the dryer season, when it is possible to walk on it, because of the root mass from the vines.

I want to put 2-4" PVC Pipes, right at the fence line, running down the slope to a spot for my water pumps-generator to be installed.

First question is, I should be able to get full pipes of water, running. Do I want to maintain the slope, OR, barely keep the full pipes running, and drop the water into the wheel, from a higher point, than if I ran with the slope. ??? ???

The slope is about 4' of drop, in 120' of run. I will dig a pit for the wheels to be below ground level, about 2' from the surface to the TOPS of the blades on the wheel.

SO, I can have 6' of drop, with just the flow from the CAPACITY of the pipes, OR, 2' of drop or less, directly into the blades, with more FLOW, almost as if they were running IN the stream. ???

Which would be better, and why ???

tyb525 · August 15, 2009, 01:18:51 PM

Are you talking an overshoot or undershoot wheel?

I believe the more slope the better.

http://www.otherpower.com/otherpower_hydro.html

http://www.reuk.co.uk/Electricity-from-Waterwheels.htm

google waterwheels

Fla._Deadheader · August 15, 2009, 01:54:28 PM

I've built an overshot wheel, but, am trying to figure the most power from the water. At 6' of grade, there is not a lot of flow, to move the wheel. At 6' of drop, I get to use the weight of the water versus the slow flow rate ???

There just is not a lot of room to utilize this small stream.

tyb525 · August 15, 2009, 02:14:04 PM

I have read of low-volume, high speed wheels, and high-volume, slow speeds wheels. A fast spinning turbine design might be more suited to you.

Also, have you considered using a water ram to take the water after it goes over the wheel and pump it back up to be used again? Water rams can be up to 80% efficient, but normally are around 60%. They can lift water almost 10 times higher than the source, with less efficiency. Example: Some rams can pump water from a stream with 5 feet of head about 50 higher back up, but the efficiency drops to around 10% usually. That is not a problem if you are using it for drinking, etc.

Fla._Deadheader · August 15, 2009, 03:19:13 PM

My Dad used to collect ram pumps, Rife Ram, to be exact. ;D

I have most things in place, to start the project. Just need to find the best way to use the water. I believe the weight is more efficient than the flow, EH ???

Where's all the DanG injunears when ya need um, EH ??? ;D ;D :D :D

tyb525 · August 15, 2009, 03:46:58 PM

Probably out sawin' like I should be! :D

Chuck White · August 15, 2009, 08:01:30 PM

Don't know much about the design or installation of waterwheels but it might behoove you to get water-rights from the neighboring farmer in writing before you soak a lot of time and money into this project.

Things to consider are "what happens to the waterway if the farm changes hands" or "the current owner may just change his mind and redirect the water somehow"!

Fla._Deadheader · August 15, 2009, 10:38:45 PM

It is located in a "draw", so, no practical way to divert it.

Ianab · August 16, 2009, 02:28:06 AM

With an overshot wheel I think you need the water to arrive at the wheel as high as possible, with as much flow as possible. Water pressure isn't an issue.

Normally they would be fed from a dam or weir via an open channel and a flue extending out to the top of the wheel.

I guess you could use a big dia plastic pipe running at ground level then coming up to the top of the wheel, as long as you had enough head to keep the flow going.

We have a couple of quite big rebuilt water wheels in local parks and thats how they are fed. One is a bit 12ft one that is just run for show, the other one (~8ft) is actually connected to a water pump that provides water for the gardens.

Ian

Fla._Deadheader · August 16, 2009, 10:39:02 AM

I built one similar to this photo. This guy has more "head" than I do, but, I have sufficient water, IF I use it to the best advantage.

I'm trying to figure the weight of water, dropping onto the buckets, versus the flow of water, arriving at the top of the buckets.

Is there much difference ???

Evidently, the Forum and Coppermine are screwed up, this morning ??? My SQL message comes up with photos, also ???

Maybe SOMEONE is messing with the program ???

SwampDonkey · August 16, 2009, 11:54:30 AM

Have you given thought to starting at the source with a larger pipe than at the spill end? That will give more force if your using a wheel with smaller collection pockets. As far as weight of water, that is constant, but force changes faster from spill to wheel with increased drop distance because of acceleration due to gravity.

Acceleration due to gravity = 32 ft/s² (imperial) or Velocity divide by Time minus initial velocity (0 if from a dead start) In this case your water as it enters the pipe is not at 0 velocity. Standard formula for Acceleration = Force divided by mass. I would think if you timed the rate of flow in seconds from the start of the pipe to the exit and divide it into length of pipe in feet you'll get an accurate velocity. It would also account for friction in the pipe.

Weight of water = 10 lbs/gallon (imperial) 8.5 lbs/gallon (US)

Velocity of water traveling in the pipe = Volume flow/pipe Diameter (expressed in feet) squared / 3.14

Fla._Deadheader · August 16, 2009, 12:48:49 PM

One last try :

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Radar67 · August 16, 2009, 12:58:21 PM

FD, that is an interesting project. Can you show some more detail on the pump part, or explain it?

I have some pictures of a grain mill in Cades Cove, TN. The water is diverted from a stream, through a trough to the wheel. The wheel uses the weight of the water falling from the trough into the buckets on the wheel to turn the gears of the grain mill. I'll try to get some of them up later today.

Your design should work fine with just the weight of the water turning the wheel.

Radar67 · August 16, 2009, 01:19:43 PM

FD, here is one of the pictures I uploaded. There are 9 total with good descriptions in my Cades Cove gallery.

ellmoe · August 16, 2009, 02:06:24 PM

Quote from: Fla._Deadheader on August 16, 2009, 12:48:49 PM

One last try : :

Harold, how much are you getting for the product placement? :D

Fla._Deadheader · August 16, 2009, 02:34:43 PM

Not my photo, Mark. ;D

This guy is pumping 500 gallons per day, 130' up the mountain. He has 1 pump. I plan on 2, for 1000 gallons per day. 2 wheels would get me 2000 gallons per day, and turn over the water in my pond in about 7 days or so.

The overflow will go back down hill, and power the Alternator. I am presently modifying that. ;D