Naked Science Forum
Non Life Sciences => Technology => Topic started by: newrobert on 14/11/2014 16:21:17
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Hi guys,
I just found big 20-30 meter diameter water wheels used to lift water in ancient time. Find some here http://www.machinerylubrication.com/Read/1294/noria-history
In ancient times human and animals were used to rotate this wheels but can we install electric motors with these wheels and lift water. Normally these wheels were slow but if this is possible then electric motor can rotate these wheels at great speed?
There are many water wheels shown here at http://sakuramochi-jp.blogspot.com/2012/04/oldest-waterwheel-in-mesopotamia.html
I am interested in getting one wheel or building one wheel like this and electric motor with it to rotate it fast.
Robert
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If your aim is to lift water, you are better off using an electric pump--these can be quite efficient. If your aim is to explode a large wet wooden wheel by spinning it quickly, this sounds like a great idea. It will take a lot of energy to get it up to speed though, especially if it is full of water.
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Keep in mind that many water wheels were for generating power, best to have a high water source that could be run over the wheel to a lower location, although they may also work simply in a fast flowing river.
For pumping water, no doubt the water wheel would still work, although perhaps a high maintenance option with the height limited to the diameter of the wheel.
As far as high speed pumping, you would run into a number of inefficiencies. You have to have a way to fill your buckets with water (have to have time to fill), get them to the top of the wheel, dump them, and spill as little as possible. Dragging the buckets in the water undoubtedly has a significant resistance, perhaps minimized by running the wheel in the same direction as the natural river flow, but that would also give you an optimal speed of the wheel based on the rate of flow of the river.
Your goal, of course, is not to make a paddle wheel like used to power early boats.
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Yes, my purpose is to lift water. I was searching on net to find ways to lift water and I found these ancient time water wheels.
I have one amusement park project where I need to lift heavy water at 200 feet height during amusement park time. Water may be like like 100,000-150,000 liter in one second from the ground pool where water will come back after processed in amusement rides/work etc.
I search how much big pumps I needed to lift this water and I found this general formula.
Pump HP = (height in feet * water flow in gallon per minute)/3960
https://www.easycalculation.com/physics/fluid-mechanics/water-horsepower.php
http://irrigation.wsu.edu/Content/Calculators/General/Required-Water-Pump-HP.php
Normal pump
100,000 liter = 26,417 gallon
26,417 gallon x 60 = 1,585,033 gallon per minute
Pumps HP = (200 * 1,585,033) / 3960 = 80,052
Pumps KW = 59,694 KW Pumps (on 100% efficiency but this will be more at 80%)
Those might be 1000 pumps of 59kw if this formula is correct.
That is huge huge investment or huge power that's impossible for us to bear or install.
Water Wheel Idea
Water wheel diameter = 74 meter
Water wheel diameter = 244 feet
Circumference = 765 feet
Two bucket at both side after every = 6 feet
Total buckets = 127x2 = 254
One bucket size = 4x4x4 feet (64 square feet)
Water in one bucket = 479 gallon
1 Bucket weight = 1,812 kg
Water lifted in one round = 121,603
Wheel speed: 1 round in 2 minutes
Round per minute: .50
Speed: 6.37 feet per second
Speed: 1.942 meter per second
Even this wheel is run by 200 kw motors that's good for us. For example 50kw motors installed at 4 sides to rotate wheel as fast as it can be with safety.
Conclusion:
Other than cost to construct this wheel, is this idea practicable? If not, scientifically what's problem in this idea. I mean same water wheel used thousands years before is constructed at big level and rotated with modern electric motors.
Please advice me.
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I think the conclusion is that you'll go broke paying for the electricity to run that thing. The water wheel will take just as much energy, or perhaps even more than the conventional pump. Although if you have a few percent inefficiency, then you may be able to play with that a bit, which could end up being a significant amount of money.
Let's confirm your calculations.
Power = Mass x (Acceleration due to Gravity) x (vertical distance) / time
Power = (100,000 kg x 9.8 m/s2 x 60.96m) / 1 second = 59,740,800 Watts, or 59,740 kw.
So, if you are paying, say $0.10 / kwh, then it will only cost you about $6,000 per hour for the electricity to run your water park. I suppose that isn't bad considering the amount of water you're moving.
I'm trying to imagine what you're building.
I was on a "log ride" at the Enchanted Forest in Salem, Oregon recently. I'm sure they use a lot of water. I'd have to look at it again. However, it has a mix of deep spots where the log boat may be floating in relatively slow moving water, and shallow spots where the water flows faster, but the log boat may actually be suspended on tracks or rollers, and some kind of a gate system between the two. The advantage of using cables, tracks, rollers, and etc is better control of the vehicle (you don't want it to ever tip over).
You may be able to simulate a waterfall using relatively little water going over glass or Plexiglas, or even rocks.
Also consider if your design is conducive towards energy recovery, for example making a hydraulic elevator that theoretically could come close to breaking even on energy usage, recovering the energy that it consumes.
Some hydroelectric power plants use a long canal system to create an elevation differential. In the end, you get cheap water power, but high construction costs.
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Cliffordk, thank you very much for replying to this thread.
I am studying big Ferris wheels around the world and "London Eye" is one of these. According to London Eye website, this wheels rotates "362 ton" weight (cabin + passenger weight) equally distributed on 135 meter diameter wheel. And 150KW motor(s) drive this wheel and due to amusement purpose one round is completed in 30 minutes.
I am confused on 2 things after reading your reply.
1. Is this water wheel idea is not practicable? If London Eye is rotated by 150KW motors then this water wheel can take 300KW to rotate a little faster i.e. one round in 10-15 minutes. Is this not practicable i.e. scientifically what's problem in this idea?
2. Can you please give me some more idea about what you mentioned at last i.e. some kind of hydraulic elevator or long canal system? What's that idea, can you please give me any hint or reference url?
Thank you
Robert
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On the "Ferris Wheels", you have about the same weight going up as coming back down, although I suppose that isn't exactly true during the loading and unloading phases. However, they often empty one carriage, and reload it, always keeping the wheel balanced. Do the wheels load the carriages sequentially during the first load in the morning, or do they have some other balancing method?
Anyway, your water buckets would be just fine if you carried the buckets to the top and then carried them back down to the bottom, always FULL. However, once you start loading at the bottom and emptying at the top, your power requirements become HUGE.
Rather looking a Ferris Wheel, perhaps you should consider a ski lift that goes up full, and comes back down empty.
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Unfortunately with "energy", there is no free lunch.
Except for those little power gremlins that eat away at your efficiency.
Say you designed a pump that was 200% efficient, then you would expect every hydroelectric plant to add one of your Ferris Wheel pumps, and start generating unlimited power. Unfortunately, one can't have perpetual motion. Movement always consumes energy (although I do find Solar Radiometers to be quite a cool, maximally efficient systems).
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Cliffordk, thank you for your reply.
1. Are you assuming that I want to lift water to generate hydroelectricity? You mentioned this twice.
2. You mentioned I need HUGE power if full buckets are going up and empty buckets are going down, what's might be that HUGE power. All what I expect is double power than normal condition. If wheel is rotating clockwise and from right side empty buckets are coming down and from left side filled buckets are going up then what if we do some arrangement to install additional motors at right side (to push wheel down to make some balance as compare to left side) from where empty buckets are coming down.
I want to calculate what is HUGE power that I may needed?
3. You did not mention what you said in one of your previous post something about long canal system idea, can you please mention something about or let me know from where to find more information about that?
Thank you
Robert
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In ancient times it was raised and filtered water with this. No moving parts, only absorption and a lowering of atmospheric pressure. Worked well until forgot what it is and how to use properly.
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The optimal power required for your wheel will be about the same as any other pump, or at least the 59,740 kw that was calculated earlier.
As far as canals, if you have a natural source of higher elevation water, it is not uncommon to build a canal to maintain the elevation. Along the McKenzie river near Eugene, there are two Canals.
1: Beginning at Leaburg Dam, and ending a few miles further downstream.
Leaburg Dam and beginning of Leaburg Canal (https://www.google.com/maps/place/Leaburg,+OR+97489/@44.1377368,-122.6126454,129m/data=!3m1!1e3!4m2!3m1!1s0x54c0c1e841bdcf1f:0xb0b69b41e7ee414d)
End of Leaburg Canal (https://www.google.com/maps/place/Leaburg,+OR+97489/@44.1014937,-122.6894495,129m/data=!3m1!1e3!4m2!3m1!1s0x54c0c1e841bdcf1f:0xb0b69b41e7ee414d)
2: Beginning at just a river diversion, and ending near Walterville.
Beginning of Walterville Canal (https://www.google.com/maps/place/Leaburg,+OR+97489/@44.0763256,-122.7664932,515m/data=!3m1!1e3!4m2!3m1!1s0x54c0c1e841bdcf1f:0xb0b69b41e7ee414d)
End of Walterville Canal (https://www.google.com/maps/place/Leaburg,+OR+97489/@44.0696767,-122.8358013,258m/data=!3m1!1e3!4m2!3m1!1s0x54c0c1e841bdcf1f:0xb0b69b41e7ee414d)
In this case, the canals are used to create an elevation differential for power generation. [img float=right]http://upload.wikimedia.org/wikipedia/commons/thumb/e/ea/Cascatemarmore.jpg/220px-Cascatemarmore.jpg[/img]
Keep in mind though. Say you had an unlimited water source, and built a canal to deliver 100,000 liters of water at 200 feet elevation. If you put that water into an ideal power generator, you would recover about the 59 MW of power that your pump would consume. Now, you could generate power some of the time, and run the water park other times.
The Cascata delle Marmore (http://en.wikipedia.org/wiki/Cascata_delle_Marmore) in Italy is even more interesting than I had remembered. It is actually a man-made waterfall from back in the ancient Roman times. Today, however, most of the time the water is diverted through a hydroelectric power plant, but on a schedule, the water is allowed to pass over the falls, and it is open for viewing by the public.
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Unfortunately with "energy", there is no free lunch.
I completely understand this, I am trying to minimize (not remove) the cost of lifting water.
Say you designed a pump that was 200% efficient,
I completely understand that its not possible and I never think about this.
Now I am thinking at another idea and I know that will be free but how much water can be lifted I can't say anything unless its calculated.
While searching on net, I found that ancient time water wheels were rotated by power of moving water in river/canals.
Since we already have a big water pool at ground so what if we build small canals like 5-10' wide and 5-10' depth and 20-30' long (or whatever is required to build pressure) and water flows in these canals and moving/flowing water rotates water wheel at constant speed (I know rotating speed will be very slow). So this is same as used in ancient times.
If required canal can be made like a slope to make power in flow. Like if canal length is 100 feet and total slope is 10 feet from start to end then 5 wheels can be installed after every 20 feet?
Even 20%-30% (of requirement or total flow) water is lifted by installing multiple wheels then its not bad deal. Is this possible?
Robert
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Just additional comments that I am not trying to make Perpetual motion machine that is impossible. What I am trying to do is to minimum cost of water lifting. I mean lift as much water as possible by these wheels (electric powered or water powered) and then use traditional pumps for remaining water. These wheels will cost one time and will save much money in long run.
Robert
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Water flow is induced by drop.
Say you add 5 feet of drop to your canals.
Then you simply have to raise your water an additional 5 feet in height which is going to require MORE energy, not less.
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Water flow is induced by drop.
Say you add 5 feet of drop to your canals.
Then you simply have to raise your water an additional 5 feet in height which is going to require MORE energy, not less.
Ohh [:o]
Then how old water wheels have been working. I saw in images that these wheels are in water without drop/slope, just when water flows then these are rotated by flow.
http://sakuramochi-jp.blogspot.com/2012/04/oldest-waterwheel-in-mesopotamia.html
http://www.machinerylubrication.com/Read/1294/noria-history
For example if there is pipe (just assume pipe for easy understanding otherwise there is canal with steady flow of water) of 5 feet diameter with 2 feet slope with full water flow and water is dropping on wheel buckets and forcing it to move, now no matter how much diameter of wheel is, will this flow of water not move that wheel?
Robert
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If you have a brook with no drop, then your wheel won't rotate.
Rapids in a river are created by water running from a high place to a low place.
It is hard to tell from your photos, but some of the wheels may be installed in a weir, which may be incomplete today, a century or more later, but when the wheels were in use, the weir directed river flow, and created the drop for maximum efficiency.
One could potentially design a Noria that is self-powered. But that would require much greater overall flow than is actually being raised. So, say you might raise 1% of the water with the Noria, and waste 99% of the water.
If you had access to an unlimited supply of water to power your Noria, then you'll do well. However, if all of the flow is artificially created, then you'll be expending energy to pump water past the Noria, in excess of the amount of energy saved by using it.
If the goal is efficiency, then add a turbine. You can build a water wheel, but it should just be for show.
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Thank you man for your help regarding this issue.
I have done some more research that's why there was break in replying to this thread. Now I am thinking on different angle and all depends on one assumption that I am going to ask you. Then I will update here some more details of project so you may have more idea what I want to do.
Can you give me your opinion about the following:
1. One 5-10 feet wide canal with at least 2-3 feet deep regular water
2. Canal length = 400 feet
3. Canal slope = 20-30 feet. It means from one side canal is starting 20-30 feet higher than ground and then on second side canal is at ground. It might be like a falling bridge.
So above is great slope and water is coming regularly without stop with full pressure.
1. Wheel and canal width is like this video I mean canal width is according to wheel so there is no extra water flowing just for nothing. Water flowing is creating force.
2. Another example of wheels is a row here at wider canal but wheel are rotating fast and lifting good amount of water. specially you can see at around 1:00 that water slope or flow is not huge just with normal water flow, 3 wheels in a row are moving. I can assume more water flow than this in my canal.
Another example here about water flow and how much wheels are dipped
So what do you think that if wheel and canal width is according to each other i.e. water is not flowing extra from right/left and there is 30 feet slope from start to end of 400 feet canal and there are 20 wheels of 20 feet diameter in a row, can each wheel lift 2%-3% of water flowing under the wheels?
There might be around 100,000 gpm water flow in a canal coming from 30 (or 20 feet if 20 feet is fine) feet height. 100,000 gpm is big flow and this water should rotate wheels very fast.
Since I want to lift water at 200-250 feet height so this is not possible to make wheels of 200-250 diameter just to lift 2-3% of water flowing under these (although earlier I was thinking to make each wheel of 200-250 diameter). Because if each wheel is 200-250 diameter wheel then for just 5 wheels I need 1100 feet canal that's very hard to manage and big wheels to manage.
Now I am thinking of around 20-30 feet diameter wheels which can move piston like this wheel and then that piston can lift water at 200-250 height. So wheels height and paddles are created in such way that water force can move piston which can lift maximum weight.
So in short do you think that 1 wheel can lift 2%-3% of flowing water?
I will update more here about my project and what I am thinking but first I need opinion on above question.
Robert
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Your wheel will work, but I'd consider it more of a decorative feature than a power feature.
Of your videos.
#1 - Only turns, no work is being done.
#2 & #3, same wheels, I think. There appears to be a small weir creating a flow restriction and a few foot drop in the canal. There are wide paddles, and small buckets. It does seem to be able to pump a fair amount of water. Any pouring of water from height is wasted energy (not bad for a theme park, but not energy conserving).
#4 - This wheel is driven from a stream being diverted from above, so the power is from the weight over water descending for the full height of the wheel. A lot of water seems to be leaking out everywhere, which would be considered wasted energy.
Anyway, all the water wheel stuff will work. But you should also consider your primary pumping being standard motor driven pumps (unless you have a large river that you can divert).
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Since I did not get clear answer so I will ask short and to the point question. :)
In reference to all mentioned above should I consider 2%-3% water lift by each wheel depending on the slide/height and water flow provided provided by wheel powered piston/pump? Or how much % you consider.
1. Water fall is 20-30 feet
2. Canal/wheel width is according to each other, no water flowing in waste
3. Water volume might be 100,000 gpm
Robert
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Hmmm,
Say you are raising the water 100 feet.
Then, optimally, with 1 foot drop, you should be able to raise 1% of the water 100 feet.
For 5 feet of drop, you should be able to raise 5% of the water.
However, I'd anticipate your water wheels to be far from optimal. I don't have the efficiency numbers, but if the wheel is, say 20% efficient, then you would get the equivalent of 0.2% of the water flow being raised 100 feet per foot of drop.
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Hmmm,
Say you are raising the water 100 feet.
Then, optimally, with 1 foot drop, you should be able to raise 1% of the water 100 feet.
For 5 feet of drop, you should be able to raise 5% of the water.
However, I'd anticipate your water wheels to be far from optimal. I don't have the efficiency numbers, but if the wheel is, say 20% efficient, then you would get the equivalent of 0.2% of the water flow being raised 100 feet per foot of drop.
Sorry man, I am not technical person, so please bear with me. [:D]
Now I can understand something but I think since wheel should be made according to requirement using latest techniques to extract maximum force from dropping water that's why I assume it must should be at least 80%+. Because wheel does not have to lift water itself, wheel have to covert force to piston. If wheel lift water itself then there are chances of leaking water while lifting, incomplete water buckets, etc.
So if I assume 80% wheel efficiency and I want to calculate first wheel and last wheel in row.
Wheel efficiency = 80%+
Water lifting at: 200 feet
First wheel = Drop 1 feet (since pool is at 20' height so vertical distance is less between top pool-wheel)
Last wheel = Drop 20 feet (since pool is at 20' height so vertical distance is higher between top pool-wheel)
Now how much water both wheel can lift. Depending on your calculation I will calculate each wheel (20 in a row) myself.
Thank you for helping me.
Robert
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If you have a total of 20 foot drop.
And are raising the water 200 feet.
Then the maximum amount of water you could pump is 10% of the water no matter whether you have one wheel or a dozen wheels, nor whether they are arranged in series or parallel (drop/(total height to raise water)). I believe that is raising the water from the lower pool. You could only use the waterwheel to raise water from the upper pool, but then you would subtract the water pumped from the total water powering the wheel, and I believe end up with the same answer.
You then multiply in the efficiency of the wheel and the efficiency of your pump.
The series wheel arrangement may have some impact on the overall system efficiency.
I think 80% efficiency would be optimistic for your wheel.
However, say you have a 90% efficient pump, and an 80% efficient wheel (or chain of wheels), then the overall system efficiency is 0.9*0.8 = 0.72, or 72% efficiency, which you can then multiply by the portion of water being pumped (10%), to get 7.2% of the water being pumped.
Your problem is that the 20 foot drop costs you essentially 10% more energy to raise the water up 220 feet rather than 200 feet. Your super-efficient water wheel gains you 7.2%, and you're still down 3% energy.
So, say a pump that took 100% of x amount of energy to pump the water 200 feet, now with the addition of the additional drop, and super-efficient water wheels now requires 103% of the original energy consumption to make up for the additional losses (or more).
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I think we should distinguish between perpetual motion which is pretty common on a human time scale i.e planets going around a star, sub atomic particles orbiting and jittering and machines that can extract useful power indefinitely from such motion.
satellites can draw power from the motion of planets via a sling shot technique but it is only a transfer of energy not its generation.