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water pumping windmill question
4

water pumping windmill question

water pumping windmill question

(OP)
Does anyone know the formula for calculating the distance a windmill will pump horizontally?
An 8ft windmill will lift water 180ft with a 1 7/8 cylinder pump. If my static water level is 60ft and the cylinder is @75FT I'm pumping up to the surface 60 ft. I would like to know how far I can pump after that point horizontally. Surely water will move easier horizontally than vertically.
other factors that may influence distance......
1 1/2" pvc pipe at the surface only
drop pipe is 1 1/2" galvanized
I'm at 220 ft above sea level
flow of water is not constant in the pipe
thank you

RE: water pumping windmill question

You say the total pump head is 180 ft.  That should be given with a corresponding flowrate. If its given at flow = 0, then that's called the pump's shutoff head and the pump's output head will decrease from that value as flow increases.  Anyway, whatever value you have, for now we call it Hp.

I'll assume your pump is a few feet above ground elevation and we'll call the pump centerline elevation Hcl.

The underground lift (water level to the ground level)
60 ft = Hw

Available head, Ha, is what's left after you get the water to the centerline elevation of the pump, so that's

Ha = Hp - Hw - Hcl - Hl

This head is "available" to force water through the discharge piping.   What's Hl?  There are some friction head losses incurred by running the flowrate (remember that corresponding flowrate I mentioned above?) through the vertical well pipe, so we have to subtract that head loss too.  There are pipe head loss tables or online calculators you can use to calculate that.  So, with the remaining head Ha of 114 ft, and that corresponding flowrate, you can determine what irrigation supply pipe diameter you need.  
Say it's 6" diameter.
Now we check it.

Let's say Ha = 180-60-3.6-2.4 = 114 ft.  Looking at the pipe pressure-head loss tables, we find for a 6" you lose 33 ft along the total length, so that's  114 - 34 = 80 ft. head remaining at the end of the supply pipe.  If that is greater than what you need to pressure the end-of-the-line sprinkler, you're OK.  If not, you need to increase the pipe diameter. and do this check calculation again.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water pumping windmill question

Need a bit more information about the pump and windmill. From your description I am assuming that it is a well mounted single piston style of pump with 1 7/8" piston diameter. What is the stroke of the piston which will provide a volumetric flowrate vs windmill speed.
The windmill characteristic will determin power output and hence how far you can lift and pump the water.

Mark Hutton


 

RE: water pumping windmill question

(OP)
HEC,
The cylinder has an eight inch stroke and will pump .0960 gallons per stroke. With a 15-20 mph wind the windmill cylinder will pump around 180 gallons an hour and the total lift this cylinder is capable of lifting is around 180 ft. Vertically I will be pumping 60 ft, once at the surface I want to run 1 1/2 inch pvc pipe over to a ground tank.  From windmill to where I want to dig the tank there is maybe a 2-3 ft elevation increase. I want to dig my tank a far away as possible so I need to find out how far this thing will pump horizonally.  thanks   

RE: water pumping windmill question

I've never worked with windmills and this forum is great at introducing our forum audience to new material.  I guess the key word is the windmill characteristic curve as pointed out by HEC.  This is the technical information the enquirer needs to have.
Also because of the pumping requirements, would the pump be sucking water vapor with a 60'lift afterall atmospheric pressure(appx equivalent to 33'water) is the driver in this lift.
 

RE: water pumping windmill question

2
Can we also assume that the mill is capable of lifting water 180 feet from the pump to ground level with little or no residul pressure at the discharge point.

If this is the case it is reasonable to assume that there  is still approx 120 ft of head (pressure) left to deliver water thru your pipe line. friction loss thru 1 1/2 PVC pipe is something like 0.2 ft / 100 ft which means you could pump thru something like 550ft of horizontal pipe with an increase of elevation of 2-3 ft.

RE: water pumping windmill question

Artsi,
You are correct in estimating the amount of pipe that the windmill will transfer based on the operating data supplied by the OP. Key here is the wind speed this is based on. From my estimates the windmill is generating around 145Watts to move the water (Vertical or horizontal will require the same amount of energy). This is at 13 - 17 knots of wind.
A more relavent question here is what is the expected average wind for the windmill? This will determine the averge performance for the windmill and therefore the pump. The information can be obtained from the Bureau of Meterorology for your area. For example Roxby Downs is not a high wind area and experiences winds of less than 7m/s (13knots) for 97% of time and is an average of 4.7m/s (9 knots). The design data given above by the OP would not be correct for the example location. Because the average wind speed is significantly less than the design wind speed the output would be lower. Assuming a directly proportional relationship for torque and wind turbine speed will give effective turbine power output of 50Watt and from this a flow of 400l/hr (105USG/hr) at 32m (104ft) head (lift). A very diferent system!
Sory about the mixed units. It comes from a mixed past!

Mark Hutton


 

RE: water pumping windmill question

Mark

Agreed, there are many variables to consider, I have just taken the case as presented 180ft / 180 GPH and assumed a steady flow which in real life it won't be - but at least this gives a starting point for consideration.  

RE: water pumping windmill question

Isn't this essentially a positive displacement pump?  The only windmill pump I've ever seen had the piston downhole, and the column had a series of flappers (check valves) above the pump.  The flow is not steady state at all.   

RE: water pumping windmill question

Believe the flappers (check valves) mentioned by RossABQ are designed to be forced into a closed position by the static head pressure.  

Where will this pressure come from when the pump is in a horizontal position?
   

At 74th year working on IR-One2 PhD from UHK  - - -

RE: water pumping windmill question

RossABQ - as stated I have assumed steady flow and have acknowledging that it won't be - but the math is far too complicated (for me) to be bothered with tryig to calculate a pulsing flow from a windmill pump subject to an infinite number of variables wind speeds.

Apakrat - the pump is vertically mounted situated 75ft below GL so plenty of static head to close NRV.

RE: water pumping windmill question

(OP)
Ok, I better explain a few things........The windmill pump is located close to the bottom of the well and has three check valves.The windmill pump is the device that actually pumps the water. Water is pumped to the surface when the pump rod raises the piston. The piston check valve closes and holds the water above the piston. As the piston rises, water is moved up the pipe towards the surface. Water is also drawn into the lower section of the pump cylinder through a screen and the two lower check valves. When the pump rod reverses and begins to descend, the lower check valve closes and the piston check valve opens allowing the water in the cylinder to pass through the piston check valve and become trapped above the piston when the check valve closes. This cycle is constantly repeated as the windmill wheel turns, operating the reciprocating mechanism in the gearbox, which operates the pump rod and pump. Now all that being said......I'm not concerned with pressure only distance. A windmill can only be operated as an open ended system, the water must go somewhere or the windmill won't operate. If my distance is too far to the tank my windmill won't turn. My only other option would be to drop down another size on the pump which would give me more lift but reduce my volume of water pumped. Thanks again for all your help.

RE: water pumping windmill question

You nailed it.  Seems like as long as the pipe is less than 500 ft or so, Artisi says you'll get some flow.... well, as long as the wind cooperates, and the pipe doesn't freeze up, etc., etc., etc.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water pumping windmill question

not sure I agree with the 500 feet calculation. according to the information given, flow rate is 180 gph or 3 gallons per minute through 1 1/2" pipe. head loss in this size pipe at this flow rate is approximately 1.5 feet per 1,000 feet of pipeline. If you have 120 feet of head being delivered by the pump, than you can certainly pump further than 500 feet.

RE: water pumping windmill question


Thank You Artisi
Sometimes my stupidity over exposes my true school'n.  

Would still like to offer a thought about the windmill delivery flow from the perspective of a proven idiot.

To verify what BigInch & CVG are saying, Ya might wanna check out---------
http://www.engineeringtoolbox.com/pvc-schedule-40-pipe-friction-loss-diagram-d_1147.html

Quote:

The cylinder has an eight inch stroke and will pump .0960 gallons per stroke. With a 15-20 mph wind the windmill cylinder will pump around 180 gallons an hour
My personal thought is based on----
Five ft. of 1-1/2" PVC has a volume of 0.459 gallons.  To reach a flow rate of 5 fps, causing a friction loss of 3 psi per 100 ft of pipe, the windmill must deliver 0.459 gal. per sec.

At 0.459 g/s using 0.096 gal. per stroke, needs 4.78 strokes per second to reach a point of 5 fps flow rate.

The 15-20 mph wind causes a stroke averaging every 0.52 seconds, (180/0.096), or for calc purposes, 17.5 mph wind causes a stroke every 0.52 seconds

Usually, a windmill will be shut down for structural safety at wind speeds of 40 mph or less.

Using 40 mph/17.5 mph = 2.786 strokes per 0.52 seconds equaling 4.395 strokes per second.  

The 4.395 strokes X 0.096 gal. per stroke = 0.422 gal. at a flow rate slightly less than 5 fps.

At 74th year working on IR-One2 PhD from UHK  - - -

RE: water pumping windmill question

(OP)
Apakrat,
 Did you mean that the windmill would be shut down for structual safety at wind speeds above 40 mph or below 40mph? Actually, the only time I shut it down is if a hurricane is approaching. This windmill is almost 90 years old and it runs in above 40 mph winds without failure. Windmills are designed to furl out of the wind so as not to spin at such a high rate of speed. When the wind picks up they will furl out and slow down but continue to pump. Even during a hurricane I will not apply the brakes but put the tail in about a 45 degree angle just to slow it down. So what does everyone think?....... dig the tank at 500ft?  

RE: water pumping windmill question

One option worth looking into is to discharge the water at a higher level than ground level and gravity flow the pumped water to your storage tank.

 

RE: water pumping windmill question

Question why windmill water pumping

Better to go with Solar Water Pumps;  Solar Water Pumps livestock producers and many other applications

Replace the (2) windmill water pumping with Solar Water Pumps: no problem, no maintenance problem.
 

RE: water pumping windmill question

Why wind turbines?  Cheaper initial cost.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water pumping windmill question

Did I mention sometimes they run in the dark?  Handy if you're above the Arctic Circle.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water pumping windmill question

Quote:

wind speeds above 40 mph or below 40mph?
Your shut down for hurricanes only is not a dispute by me.
Just used a guestimate based on grampa's home made wind gage used some 60 plus years ago and info the Internet wind generator people publish.

Quote:

So what does everyone think?....... dig the tank at 500ft?
My view of condition at 500 ft.  The friction loss, when the wind is at 40 mph, is estimated at 4 psi per 100 ft or a total of about 46 ft of loss from original 180 ft height.

This drag, during high wind conditions, could be considered a positive feature, actually acting as a drag-break.

Story-  On record are two young Aggie graduates purchasing a large ranch near Jal, NM back in 1968.  Seems the ranch had a windmill on about every other square mile an 15" deep native grass except for a circular grazed out area around the windmills.
The young owners scattered water troughs around the total grazing area, connected by gravity flow to the windmills with 3/4" black ABS pipe.  Stay with Your windmill.

At 74th year working on IR-One2 PhD from UHK  - - -

RE: water pumping windmill question

" BigInch (Petroleum) 6 May 09 12:16  
Did I mention sometimes they run in the dark? "

The best reply in Eng-Tips so far this year lol

RE: water pumping windmill question

All great discussion, but you are still missing the point. Where is the windmill operating and what are the prevailing wind conditions? This will determine the best location for the tank. Especially given the power from the turbine (windmill) will drop off approximately with the square of the windspeed. This will not only affect the volumetric flow but also the lift/discharge pressure available.
For the OP 500 ft of pipe is correct if your average wind speeds are around the 15 - 20 mph most of the time. If the winds are less than that for most of the time the windmill will sit there and stall. So the prevailing wind conditions will determine the maximum length of pipe that can be used.

Mark Hutton


 

RE: water pumping windmill question

HEC, Oh no.  We're not missing the point and ...

Well ... not exactly.

First, as long as there is wind enough to lift the water to the surface + a bit or so, water will flow in a 1-1/2 inch horizontal pipe.  The question then becomes not where to dig the tank, but how big to dig it.  With a pipe inlet head of only 1 ft or so, a pipe length (from 0 to ∞) , you will get a flow, which will be anywhere from 0 to a theoretical max of
piston speed * x-sectional area.  smile

So, since now I managed to make this a question of only how big to make the tank, it demonstrates that tank location is independent of distance from the well head.  I guess that's why when you see those nice artistic senia-colored photographs the stock tank is always in the immediate vicinity of the windmill.  So, I go back to what Artisi said, "gravity flow to anywhere".  If you had a 180 ft tall tank, you could pressure flow if you wanted to too.  But he wants his tank far away for some reason, so add some pipe.

P.S. when I run these tiny flowrates in my Churchill program, I get only a few feet head loss, so I'm ignoring the system curve and

Then figuring only a known pump power from the wind and lifting to various heights above static water level, I get these flowrates, attached.  Of course the pipe system curve should be added to be technically correct, but I have to do something other than this today.

 

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water pumping windmill question

BigInch,

Sorry if I caused offence, it was not intended. I do follow your argument, however if the discharge pressure on the pump is too high the pump/windmill will simply stall. There will be a maximum torque along the constant power curve where the turbine speed will be too low to keep it spinning and the pump will stall. The design point given by the OP is for a "moderate breeze" (4 on the beaufort scale). For some areas this is a good mild day, in relation to wind strength. In other areas the normal wind strength may be much lower, in which case the windmill will be stalled most of the time. This is my point.

Mark Hutton


 

RE: water pumping windmill question

my two cents - from the information provided, lift is 60 feet and pump will theoretically lift water 180 feet during a "moderate breeze". So there is 120 feet of resultant head which equates to approximately 50 psi at the ground surface. even though we don't have a pump curve it is reasonable to assume that the windmill will continue pumping water perhaps to the point that the wind decreases to a "light breeze" while still providing at least a few psi at the top of the well. Since the friction loss in the pipe is quite low at the design flow of 180 gallons per hour and would be even lower at reduced flows, the windmill should continue pumping, at a reduced flow rate even in a light breeze. If a light breeze cannot be maintained for any length of time, than perhaps a solar collector, water wheel or team of horses would be a more appropriate power source for your pump.

RE: water pumping windmill question

http://www.cometwindmills.com.au/C_Pat%201%20&%204.pdf

Gravity flow seems the best way to go, look at figure 2 on the above link which shows the discharge from the well above ground level - using this arrangement with the tank at ground level I guess the distance the tank can be form the mill is infinity.

The question really comes down to how far can the pumped flow that is varying from 0 to theoretical max be delivered thru the 1 1/2 pipe line at the variable pressures at the the well discharge enabling a reasonable flow to be maintained with all the variables acting on such an installation?  

 

RE: water pumping windmill question

(OP)
HEC and CVG you are both on the right track, somewhat. HEC, Windmills will always stall whether I'm pumping directly to the surface or pumping a long distance, that is something I cannot control. Windmill owners realize that the windmill will pump 4-5 hours full capacity  out of 24 hours. We choose the size of pump based on our water needs knowing that the wind will not blow 24 hours a day. I could have gone a high as a 3" pump which would have delivered 320 gallons an hour at the same wind speed and depth. It is more advisable to go with a smaller pump than needed as it is easier on the windmill motor and the windmill will continue to pump at slower wind speeds.
ARTISI, gravity flow is an option. Now we have another question..........If I were to to use gravity to flow to my tank 500' how high would I need my discharge at the windmill to keep it flowing at a resonable rate in 1 1/2" pvc pipe? I LOVE THIS FORUM!

RE: water pumping windmill question

(OP)
CVG, You stated that there will be 120 ft of resultant head wich equates to approximate 50 psi at the ground surface, is this correct? Please correct me if i'm wrong, the head psi would be determined by how many feet of water is in the pipe above the discharge point. This is an opened ended system. The windmill pulls the water to the surface and the water then flows  horizontally. Where will the head pressure come from? Would I now need to install a stuffing box? I could also extend my head pipe (the pipe above the discharge point). My head pipe is 4' above the discharge point. I could extend it to about 20' above the discharge point or install a stuffing box.  

RE: water pumping windmill question

How about a tank at the mill at some pre-determined height which you can freely pump into, no stalling of the mill and it also ensures maximum capacity under all operating conditions - from there it can flow by gravity to the distant tank way off in the never-never.

As we don't know the mill flow rate at a head of lets say 80ft (standing water level to the discharge into the primary tank) how about assuming 5GPM - (no need to consider minimum flows) the flow thru your 1.5" PVC line from the primary tank to the final point is a function of the friction loss / distance / head available in the primary tank.

Using 1.5" sch 40# PVC pipe friction tables the head loss at 5GPM is 0.2ft / 100 feet of pipe run.

Therefore, calculating with a head in the primary tank of 20ft the distance from the primary tank to the final destination can be:

20 ft (head in the tank) / (0.2 friction loss per 100ft of pipe) = 100 x 100 = 10,000 ft pipe run.

If the final discharge point is lets say 3 ft above ground level the the available head reduces to 17ft / 0.2 x 100 = 8500ft pipe length.

You will need a stuffing box at discharge of the rising main from the well.  

RE: water pumping windmill question

HEC, No problem.  

Maybe I just don't understand how you're using the term "stall".  The usual IC engine interpretation is stop working, in which case I would assume flow = 0 and windmill rpm = 0.  But for a windmill (with wind) rpm not stopped and a power input of P = k * Q * H / eff, and it means H is Max and Q is min for the current wind power output. Theoretically meaning Q and rpm cannot = 0, unless H went to infinity and the pump exploded, OK, yes.

Artisi,

Yes. inovermyhead almost gave the answer.  He says "If I were to to use gravity to flow to my tank 500' how high would I need my discharge at the windmill to keep it flowing at a resonable rate in 1 1/2" pvc pipe? "
Theoretically as you approach zero flow, the distance you can flow approaches infinity, so the  practical limit is found when you know what minimum flowrate is acceptable to you.  (While still recognizing that lower flowates can and will occur, at least until you get to the point where pipe discharge head equals the back pressure on the pipe outlet, if ever.

He just didn't say what value he considers "reasonable".

CVG,

The 50 psi you mention is the maximum pressure, when Q = 0 "stalled" condition.  The pressure could be much less, almost 0 psig, if system Q is max at pump runout flow.

Artisi,

Might be OK, IF 5 gpm is inovermyhead's idea of THE "reasonable" flowrate.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water pumping windmill question

actually, the 50 psi is with Q=0 and wind blowing at a moderate breeze. This would be the assumption if you installed a shutoff valve at the top of the well (which I don't recommend doing) and then closed it. The windmill would continue to spin and try to pump but since the valve is closed, it would generate pressure, but no flow. Eventually, either the windmill would stall completely or you would blow out the pump.

See link and attached file

http://www.engineeringtoolbox.com/positive-displacement-pumps-d_414.html



I'm not sure what a stuffing box is but you should be able to just run your pipe directly from the well to the tank. I really don't see an advantage to using gravity flow which would require an additional tank or standpipe at the windmill.
 

RE: water pumping windmill question

As I see it, if you can use gravity flow, you can lift and store as much water in the nearby tank as possible at any given time, since there would not be any backpressure on the pump, ever.  It would always lift as much water as possible to only the height of the tank level and thereby maximize flowrate for that head.  Then with gravity flow, you just design that pipe for whatever flowrate you want to move to some other place.  Gravity costs nothing to use and won't come with the potential to reduce your potential supply from the well at the expense of increasing the pipe inlet head to move more water farther away.  In other words, never any pipe friction losses burned up by pump head.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water pumping windmill question

there are several reasons why gravity flow would not be beneficial.

1) ground elevation at the windmill is 2 - 3 feet lower than at the site 500 feet away. since the two tanks would be hydraulically connected, water surface elevation in the two tanks will eualize and be nearly the same. This will result in a a) remote tank which will not fill to the top, or b) you have to excavate the remote tank 3 feet into the ground to install it or c)you need a taller tank at the windmill in order to completely fill the remote tank.

2) Head loss (back pressure on the pump) to convey the water to the remote tank is approximately the same regardless whether it is pumped or flows by gravity. Gravity does not move water without a differential in head. Approximately the same pumping energy is required either way. Since posative displacement pumps have a nearly vertical pump curve, pumping rate does not vary much with pressure (see the reference I attached previously).

3) Depending on the head differential in the two tanks and the pipe size, it might take quite a long time for the water to move to the remote tank. This would require significant capacity in the first tank.

3) Two tanks will require more capital expenditure and more O&M.


I guess the main benefit of two or more tanks is that you can store water in case the wind stops blowing.
 

RE: water pumping windmill question

cvg

The point was to have the primary tank located next to the mill elevated well above the final discharge point so gravity flow could take place, also the primary tank only needs to be large enough to retain a theoretical maximun flow from the mill which exceeds the outflow - a function of available head in the tank /friction loss/flow rate.   

RE: water pumping windmill question

artisi
elevating tank 1 so that it can flow into tank 2 is certainly an option.  However, the pump still has to work just as hard to pump up to elevated tank 1 as it would to pump directly to the remote tank 2. And according to the OP, the pump has plenty of capacity to do it. So unless you need the extra volume of storage in two tanks, than what's the point of spending the extra money for two tanks?

RE: water pumping windmill question

I think the true benefit of a totally unrestricted pump discharge is that usually where you find these applications the most important consideration is to have access to water, any water, and the maximum amount of water possible.  At least that's how it was down in Laredo and here in Spain too.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water pumping windmill question

BigInch - where is Don Quixote?

RE: water pumping windmill question

He can be found in any Spanish bookstore.

Thought you were going to get me on that one, didn't you?

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water pumping windmill question

And on the web.  Since it was published in 1645, there are no present copyright worries that I know about, so its available as a free download from,

http://www.gutenberg.org/etext/2000

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water pumping windmill question

I started reading it about 6 months back in the original translated version and can tell you it is tough work - finishing it appears to be a long term project.  

RE: water pumping windmill question

No pain, no gain.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water pumping windmill question

More like brain strain.

RE: water pumping windmill question

Quote (inovermyhead ):

My head pipe is 4' above the discharge point. I could extend it to about 20' above the discharge point or install a stuffing box.  

Quote (Dave):

I'm not sure what a stuffing box is _______
http://en.wikipedia.org/wiki/Stuffing_box In a conventional stuffing box, the seal itself is provided by packing rings, or a square cross-sectioned rope, made of greased flax, which is packed or wound tightly around the propeller shaft, sucker rod, and compressed in place with a threaded nut and spacer.

A stuffing box causes a negative, (drag), impact on the windmills capability.  

Extending the head pipe 20', increases the difficulty of pulling sucker rods to get access to a pump during maintenance.

At 74th year working on IR-One2 PhD from UHK  - - -

RE: water pumping windmill question

" Extending the head pipe 20', increases the difficulty of pulling sucker rods to get access to a pump during maintenance."

The way round this problem is to use a rising discharge pipe fitted to the well-head external to the mill support frame,ie, 2 x 90 bends or similar.   

RE: water pumping windmill question

Quote (Artisi):

use a rising discharge pipe fitted to the well-head external to the mill support frame,ie, 2 x 90 bends or similar.
True, but, then a stuffing box is needed, thus building in a negative drag on the windmill.
  

At 74th year working on IR-One2 PhD from UHK  - - -

RE: water pumping windmill question

[quote True, but, then a stuffing box is needed, thus building in a negative drag on the windmill.[/quote]

Do you really think you would be able to measure any significant drag on the mill pump rod as compared to other losses in gearbox and linkages etc.

RE: water pumping windmill question

Yes    smile

At 74th year working on IR-One2 PhD from UHK  - - -

RE: water pumping windmill question

Well at least it comes free thumbsup

RE: water pumping windmill question

I just got in on the tail of this but it looks to me like Apakrat has it right. That is you either need a stuffing box or to raise the discharge pipe up high on the windmill or the so called lift of 180' is never fully developed. Otherwise the mill will just raise enough head to spill out of the top end of the pipe. From my childhood memories, this distance is normally only about two feet which is not very much head.

RE: water pumping windmill question

Yes.  But remember its doing that at considerably higher flow than when its lifting to 180 ft.  k * Q * H is constant for a given wind speed.  Go for high Q's and H reduces.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water pumping windmill question

remember this is a posative displacement pump. the discharge curve vs head is nearly vertical. In other words, you get nearly the same flow rate, regardless of the pressure. Regardless of whatever you do to reduce the drag on the pump or how high you make your tank, output will still remain nearly constant with any given wind speed. The biggest variable is the wind speed. If you want to increase output, siting the windmill where the wind is the strongest should be the number one priority.

RE: water pumping windmill question

Quote (CVG):

- - - - siting the windmill where the wind is the strongest should be the number one priority.
pipe Then connect it to a generator.
But, me thinks the number one priority would be to site the windmill at the best supply of water.

At 74th year working on IR-One2 PhD from UHK  - - -

RE: water pumping windmill question

well, apakrat, that goes without saying that there must be water within reasonable depth. and what is the point of the generator comment?

RE: water pumping windmill question

Windmill pump curves for 3 models.


I've flipflopped it for you into typical centrifugal format.


Which look a lot like the power curves in my diagram attached above.

While they are "vertical"ly oriented, they are not so nearly as vertical as the typical pd pumps we usually see and with these there is quite a lot of variation in flow vs head.  In fact flow variation with head doesn't look very constant at all no matter which way you flipflop the curves.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water pumping windmill question

inovermyhead,
I'm thinking about purchasing a water pumping windmill to maintain the water level of my pond.  It was interesting to read the different thoughts regarding your application.  Just curious how your project worked out.  Thanks.

RE: water pumping windmill question

inovermyhead,

Maybe I'm just trying to over simplify the obvious but you will be the only person who can determine what an acceptable flow rate, be it GPM or GPH, at at acceptable distance will be, which seemed to be the original question. It seems that with all the variables involved it may be easier to just purchase some piping, preferably where you can return any unused for a refund, connect to the windmill, layout at different distances and each time check the flow output at different wind speeds. When optimal flow + acceptable wind speed + acceptable distance is achieved "X" marks the spot (of + aw + ad = X).  

RE: water pumping windmill question

(OP)
mrodee,
  I'm glad you asked! I'm wondering if I should start a new thread or stay here. I had decided to change the location of my earth tank and gravity feed my water to the tank. Now, I have a whole new set of problems.......My tank is now about 1/4 mile away from the windmill and I am gravity feeding the water to it. There is about a 30ft difference in elevation and my flow rate is pretty good. My output at the tank is slightly more than my output at the windmill in about a 10-15mph wind. The problem I am now trying to overcome is my 1/4 mile long drain pipe is airlocking at times. To overcome the problem I installed 4 flapper type check valves along the 1/4 mile run of pipe and ran a pipe over to my submersible pump hooked up to a landscape timer. WOW! This is getting complicated! See if you can follow.... When the timer comes on around ten in the morning the wind is usually blowing so the windmill is pumping, it only comes on for 2 minutes. This causes the 4 check valves to close which pressurizes the 1/4 mile long pipe and then shuts off. When the pressure drops in the line the check valves open allowing air to enter which keeps the 1/4 mile line from airlocking.(sometimes) I have not worked all the bugs yet and would like to get some thoughts from others...Any Ideas?  

RE: water pumping windmill question

Can you sketch the system showing levels and positions etc, scan it and attach as a file - it would go a long way to clarify what you are trying to achieve.

RE: water pumping windmill question

inovermyhead,
I'd like to find out more information about your windmill (make, size, where you bought it, etc.)  This probably isn't the forum to do that.  How can I get a hold of you?  Thanks.

RE: water pumping windmill question

(OP)
OK, see the attached files of my setup. I used my GPS to determine that there is about a thirty foot drop from the bottom of the 1000gal poly tank to the output at the earth tank. When I first hooked it up, it would airlock every day, now, with the ck valves and timer installed it's better but I'm still not satisfied. There are two reasons for the ck valves, since it is a gravity feed system similar to a sewage drain... #1 air needs to enter the system to keep a suction from starting and creating a vacuum. #2 When my timer turns on ck valve #2 needs to close to keep water from entering my 1000 gal poly tank instead of flushing any trapped air out of the 1/4 mile pipe. All the other ck valves close at the time pressured water hits them on the way down the hill, then re-open as soon as the pump turns off. Also, if the wind didn't blow for an extended period of time I could reset my timer and allow my submersible pump to fill my water troughs and tank. I am assuming my problem starts at night when the wind quits blowing and the system drains completly. In the morning when the windmill starts to pump it does so slowly until the wind picks up, I'm assuming  air gets sucked into the system and a airlock is created. The piping from the submersible pump to the windmill has been buried for about 20 years so I am unable to check for low spots there. At this time all the other pipe is laying on top of the ground and I will not bury it until I am satisfied the system is going to work. Any input would be greatly appreciated.  Thank you.

RE: water pumping windmill question

Don't use GPS for elevation measurements.  They can be way off.

**********************
"Pumping accounts for 20% of the world's energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies) http://virtualpipeline.spaces.live.com/

RE: water pumping windmill question

please explain why you need the "check" valves on a gravity line. there is no possibility of reverse flow, so they should not be necessary. However, looking at sketch 2, it appears they are located at water troughs. Do you somehow operate these valves to divert flow into the troughs at each pasture? The breather pipes are necessary and you need one at every high point in the line to allow air to discharge and prevent vacuum from forming. Your airlock is caused by trapped air in a high point of the line, a breather pipe should be added at all the remaining high points. A detailed profile of the pipeline created using a surveyors level (not GPS) would be beneficial to solving your problem.

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