shaks

Thank you everyone for helping regarding my project.

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 in this thread. Then I will update here some more details of project so you people 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 water coming non-stop

2. Canal length = 400 feet
3. Canal slope = 30 feet. It means from one side canal is 30 feet higher than ground and 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 https://www.youtube.com/watch?v=99oH5rizH7k
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 wheels are rotating fast and lifting good amount of water. https://www.youtube.com/watch?v=XAwQWJJqxwI 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 https://www.youtube.com/watch?v=h89GLpOABzs

So what you people 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 20-30 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 flow water?

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 flowing water (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 https://www.youtube.com/watch?v=YYxansqNH7A 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.


Shaks

You did get an answer.

You have got the same answer repeatedly.

It takes at least 49KW

No, I am not looking for this answer. Can you read previous posts/

Shaks

Shaks

What is the water going to be used for?

Water is used for some amusement rides/boats/etc at different heights like 100 feet high.

Shaks

The pictures I saw used the water flowing past the wheel at the bottom to power it. In that situation it would be still one of the best.

You yourself (and another person also) mentioned this idea and I thought it will help that's why I am working on this.

Anyhow thank you for you time, I am sure someone will help here.

Shaks

You'd be lucky if you would lift even a fraction of the water rushing past the wheel. say 5% would be a guess.

So, you can't help anymore regarding calculating force of flowing water.

The purpose is for example lift as much water as it can be by installing like 10 wheels in a row. Same water is flowing and each wheel is lifting some water. Installation cost of these wheels is one time cost however pumping cost is daily running cost.

So first attempt is to make such setup which can lift water by consuming less electricity (not free, I said less) as compare to traditional pumps. Even if 10 wheels can lift 30%-40% of total flowing water (like 20,000 gpm coming in main pool and then flowing out towards wheels) then its not bad deal. And rest can be lifted with some other mechanism or traditional pumps. In this case at least 30%-40% pumping cost will be saved for forever.

Anybody help here?

Shaks

5% would be a guess.

If each wheel can lift 5% of water flowing under wheel, then its not bad deal. 10 wheels x 5% = 50% of total water coming out from main pool.

Shaks

Could it be done through evaporation/condensation?

No, it can't be. Powering water wheel with flowing water is good idea, I want to work more on this. I mean want to find force of flowing water and then calculate at what speed water can rotate water wheel to lift water.

Shaks

Don't they pump that water up to the top of the rides again?

Look up turbines and pelton wheel.

http://www.hidropower.si/en/products?gclid=CMvxzse-n8ICFRNvvAod0akA8w - there will be plenty of ideas.

Wonderful, I started this thread for same purpose to develop such setup to lift water which take less running cost as compare to traditional pumps.

Turbines and pelton wheels are irrelevant for current project. How do you connect these to lift water without using electricity?

Shas

Don't bother, for unless you have ground that is continually falling away you are not getting any water to flow. You have to have a specific geological situation to work with and obviously the bottom of a water slide is ridiculous to start with.

Unless you tell me that the water is wasted from the bottom of the water slide, you can't go and take 100 tonnes of water away every 10 minutes.

Water from all slides/rides is collected in a central pool from where we can take it anywhere. Its around 20,000 gpm (gallon per minute) coming in central pool. I did not mention to start from bottom of water slide.

Any idea how to calculate force of flowing water i.e. we can make geological location according to requirement. You give you idea how it should be to achieve the goal?

Shaks

I found this http://www.nws.noaa.gov/os/water/tadd/images/WaterPhysics.pdfand reading, might be there is something related to my concern.

Shaks

The diagram looks silly, that 2nd cube of water - where does the height of this come from?

Actually I create this diagram in hurry because I will be busy and can create proper diagram with amount of flow after few hours so I posted it so I can get some feedback while I am out. Ignore that I will create that again and make it equal to canal height. Make it wider so water stores there and then flow out with pressure. There is also idea to make canal a little narrow at end to create pressure.

Hopefully you got the idea/concept, what do you say about this, will this work something. I mean create pressure with slob and some kind of physical building and canals and then water moves to next wheel.

Shaks

On the similar sakia, but may help with the numbers:

 

http://pdf.usaid.gov/pdf_docs/PNAAM711.pdf

 

This is good info and I will try to explore it.

The pictures I saw used the water flowing past the wheel at the bottom to power it. In that situation it would be still one of the best.

I like this idea. The first priority is to "rotate water wheel" with "flowing water". Now the question is how much water required to rotate such wheel? I mean following:

1. How much water flow required

2. Above water flow can rotate how big wheel

3. How much water can be lifted in one round

I think this is good idea, I created one diagram of my idea regarding flowing water.

Will this work i.e. we can create slob to create pressure in water flow so wheel may be rotated but the question is how to measure force of flowing water?

How to measure force of flowing water or kinetic energy or potential energy of flowing water?

Any idea on this?

so just calculate how much energy it will take to raise that mass of water that height, and then power required depending on how fast you want to do it.

What are equations to calculate "energy" and "power" as you mentioned?

Shaks

There is no answer that can be calculated. You can work out how much energy is required to lift that amount of water that height and at least double it to overcome inefficiency due to friction and viscosity of the water.

Everyone says this but no one mention all steps how to make correct calculation? Can you tell me?

I want to calculate water wheel on "circular motion" rules not "linear motion" rules. If you want to help, you can tell me from where to start and how to find required power to rotate?

Shaks

so why are you asking again?

Simple, because still I did not get answer. If you have reply here.

You're going to need a lot of gearing to get an electric motor reduced down to 1 rev /10 mins Do you want to lift 10 tons of water every revolution? It would have to be a very heavy wheel, so how many horse power will that take to move?

I am looking for same answer.

Wheel diameter: 30 meter

Water mass: 100,000 kg

Speed: 1 round in 10 minutes

Driven by: electric motor

100,000 kg water = 26,417 gallon per round (1 gallon = 3.78541 liter/kg)

26,417 gallon / 10 minutes = 2,641 gallon per minute (gpm)

I found formula of calculating pump power according to gpm.

Motor HP = (height in feet * gpm) / 3960

Motor HP = (98.42 x 2641) / 3960 = 65.64 HP = 48.95 KW

So if traditional pumps are used to lift 2,641 gpm then estimated 48.95 KW motor is required.

Any idea if same amount of water is lifted by water wheel then how much electricity will be required?

I believe that moving wheel from rest to required speed will take same electricity but once wheel get momentum then it should take less electricity to keep that momentum/speed?

Shaks

I have one project of developing setup to lift heavy water at some height. A setup that take less energy as compare to traditional water pumps. I was searching on net and I found giant "water wheels" of ancient times to lift water.

Like this one http://en.wikipedia.org/wiki/Norias_of_Hama

Is this possible to rotate this with electric motor and make setup to lift water which is efficient than traditional water pumps?

I was thinking that due to circular motion, inertia, momentum, centripetal force, etc might be this can be more efficient than traditional water pumps!. I thought it may require more power to move it from rest but once wheel gets momentum then it requires less power as compare to moving from rest.

For example:
Wheel diameter: 30 meter
Water mass: 100,000 kg
Speed: 1 round in 10 minutes
Driven by: electric motor

I don't have any physics background so please excuse me if you feel this is stupid idea.

Please give your opinion on this?

Shaks

They can't lift it because the force of gravity is too high but they can push it because that force is mediated by the wheel assembly so all they have left to overcome to move perpendicular to the gravitational force is the inertia. Once this is overcome that effort is stored as momentum and that's what keeps it going and makes it feel easy; in gravity-free space that stored momentum would keep the car going indefinitely without any more pushing because there aren't any frictional forces to slow it down.

This is the easiest answer to understand for a beginner like me.

Thank you everybody.

Shaks

Hi guys,

I am thinking what science is behind this case.

Why 2 men can't lift a 2 ton car but same men with same force/energy can push same mass car for even 1000 meters.

Second question is why at start pushing a car requires more energy but later once moved it requires less energy to push same car.

Can anyone throw some light on this?

Which scientific forces are involved in this and any other example of same forces in our common life?

Shaks

Thank you for replying and helping me here.

I am not professional scientist and just trying to learn what is need to calculate in relation to ferris wheel.

Total Mass: 600,000 kg (rotating weight i.e. rim, spoke cables, cabin weight, riders weight only)
Spoke cable mass: 180,000 kg
Rim/rider/cabin Mass: 420,000 kg
Radius: 53 meter
Speed: 0.55 m/s

Interia-Rim(I) = 1,179,780,000 kg/m2 (420,000*53*53) (rim weight * radius square)
Interia-Spoke(I) = 168,540,000 kg/m2 (1/3*(180,000*53*53)) (1/3 * (spoke cables weight * radius square))
Total Interia of wheel (I) = 1,348,320,000 kg/m2 (1,179,780,000 + 168,540,000) (Interia Rim + Interia Spoke)

Angular Speed (w) = 0.01044 rad/s (.554/53) (speed / radius)

Mass of wheel (m) = 600,000 kg (420,000 + 180,000) (rim weight + spoke cables weight)

Angular Momentum (L) = 14,082,304 kg m2/s (1,348,320,000 * 0.01044) (Wheel Interia * Angular Speed)

KE-Joules (Rotational) = 73,540 NM (1/2 * (1,348,320,000 * (0.01044*0.01044) )) (1/2 * (Wheel Interia * Angular Speed Square))
KE-Joules (Usual) = 91,925 NM (1/2 * (600,000 * .554 * .554)) (1/2 * (Wheel total mass * wheel speed square)
KE-Total (Rot+Usual) = 165,465 NM (73,540 + 91,925) (Kinetic energy rotational + kinetic energy usual)

Force = 16,873 kg meter (165,465 / 9.80665) (total kinetic energy / gravity)
Newton = 3,122 N (165,465 / 53) (Total kinetic energy / radius)

@studiot, please guide me where I am wrong.

Shaks

Hi,

I tried to make calculations about ferris wheel on basis of one example of bicycle. Lecture 22, "Rotational Kinetic Energy" starting from page 2. Please see here http://rockpile.phys.virginia.edu/arc00/arch22.pdf

I am sure, I am not calculating correct, please guide me where I am wrong.

Thank you

Shaks

Hopefully this is not a real wheel for real passengers, but only an exercise?

 

In which case why is it not in homework help?

Sorry man, please move there.

Hi Guys,

I am pleased to join this forum to learn something from experienced guys and thanks in advance for helping me to understand physics.

I am trying to design a Ferris wheel with maximum SPEED and maximum PASSENGER capacity. I want to know formula to calculate MOTOR POWER IN KW to rotate that Ferris wheel. Here are general specs of the wheel.

Diameter: 106 Meter
Radius: 53

Wheel total weight: 1000 Ton
Exclude Wheel standing structure: 30%
Rotating Wheel weight: 700 ton (Everything including spindle, hub, bearing, spoke cables, rim, cabin, riders weight, etc)
Minutes Per Round: 10 (1 round completed in 10 minutes)
Round Per Minute: 0.10
Wheel Speed: .55 meter per second

For this calculation if only rim, spoke cables, cabin/rider weight is required then you can make rough estimate what might be the weight of spindle, hub, bearing, etc. which are creating force. You can make an assumption and then calculate on that assumption. I will fix formula in Excel as per given here and then adjust weight.

I want to know
1. What is total torque generated by wheel (Newton Meters / Joules)
2. What power motor in HP or KW I needed to rotate this wheel

Once I get formula then I can set that formula in Excel and try to change speed to find good results.

Please help me.

Thanks

Shaks