How much Power..?

[ruggerodk]

I've got a fairytale too:
...
Flintstone's Car is rolling 40 RPM.

If Flintstone rest his feet in the windshield, Flintstone's Car don't roll.

To make it roll, Flintstone has to put his feet on the ground and do some musclework.

How much leg-work does Flintstone has to do?

Science doesn't know?

Apart from that, Greendoor, you have nicely managed to turn around my question.

The question I'm asking is (in your story) is:

"If you allways wanna have 100 cans in the fridge.
How many cans can you possibly sell per day? And how many do you have to put IN to the fridge per day?"

regards
ruggero

[justsomeone]

Jim-Mich and Greendoor, You both patiently and respectfully answered Ruggero's question. Sorry it is falling on deaf ears. I thank you for your answers.

[ovyyus]

Ruggero, everyone seems to miss the point of your question? How about asking like this, "how much work does it take (assume zero losses) to accelerate an 8000lb 5 feet radius ring up to 45 RPM?". Some people seem to have load on the brain :D

Ovyyus - sorry, forgot you were Australian and need to have your hand-held through each and every logical thought process ...

Genius

[ruggerodk]

;-D
Ovyyus...you just nailed it! Thanks again.

That's exactly the point: They can't see the woods for the trees.

If nobody hear the question, who am I to expect an answer?

PS: A puttery-wheel is also a flywheel..and any artist will agree that it do indeed stop very quickly if you don't kick some power into it all the time.
PSS: Some genius engineer (or a lazy leg-less artist) connected a small electrical motor to the potterywheel, to give it a continous speed....maybe I should ask him?

regards
ruggero ;-)

[jim_mich]

Ruggero, so far with all of your questions you have NOT provided enough information to produce an answer. So let us start over from the beginning.

Can anyone help me with calculating the power of a 10 foot wheel, rotating some 40-50 RPM and having 8 weights of approx 1000 lbs each...?

How much power do you need to make a 10 foot, 800 lbs wheel turn 40-50 RMP?

Since you say "power" I must assume that you want to know "horsepower".

Horsepower is a measurement of the rate of energy being produce.

To calculate horsepower requires that you know three things: Force. Distance. Time.

Also when calculating horse power you have two scenarios. The first is accelerating the wheel up to some specific speed. Any amount of horsepower will accelerate a wheel up to speed as long as it is greater than the friction. A small input of horse power will require a much longer time to get the wheel up to speed.

The second scenario is maintaining that speed. From your later replies it seems that you want to know how much horsepower is needed to maintain a speed. Once again to maintain a speed requires only enough horsepower to overcome friction so that the wheel doesn't slow down.

What you seem to keep asking is how much continuous horsepower the wheel will produce. This requires that we know more information than what you have supplied. We need to know how much energy is going into the wheel or how much energy is leaving the wheel. And we need to know how fast it enters and leaves.

Horsepower is a compound measurement of both how much energy is involved and how fast that energy is applied. It is like measuring the rate of flow of water. You need to know the speed and the volume and the time. Your original question was similar to asking, "What water flow rate can I get from a swimming pool?" The answer is you can get a small flow through a garden hose for a long time or a large flow though a fire hose for a very short time.

But then you changed the question and you want to know how much continuous flow you can get. This requires we know how fast replacement water is added back into the pool.

Maybe the Wiki can help you? See wheel output.

[ruggerodk]

Can science tell how many horses (horse poser i.e.) is needed to turn these wheels one RPM?

10 rpm?
50 rpm?

I don't know the weight or dimension of these applications,...but does it really matter?

ruggero ;-)

[jim_mich]

I don't know the weight or dimension of these applications,...but does it really matter?

Yes, it really matters!!!

You say you are an artist (graphic designer). How much paint is required to paint a picture?

The answer is that it depends on the picture size and on how thick the paint is applied and how much of the picture area gets painted. Is the picture a billboard or a postcard? Are many colors used or only one? Do you use watercolors or oil paints?

[ruggerodk]

"What water flow rate can I get from a swimming pool?" The answer is you can get a small flow through a garden hose for a long time or a large flow though a fire hose for a very short time.

But then you changed the question and you want to know how much continuous flow you can get.

Jim..I must acknowledge you do a hell of a job to explain things.
Unfortunately you too seem to miss the point, as you focus on wrong factors.
And I only changed the Q to an opposite scenario, as noone seems to be able to calculate the other way around. But it's actually the same Q turned upside down (Input = Output).
A swimmingpool is a very finite and limited reservoir which does not reflect the scenario of my Q.

The main premises are:
We have a heavy wheel running continously at 40-50 RPM.
We don't know the power source...and we don't care either...as it will be available (infinite reservoir) at all times.

That is:
We know the weight, size, and time.

Why do you keep asking for INPUT force?
Is has no relevance.
Call it "X" for what I care...a constant.

regards
ruggero

[ruggerodk]

I don't know the weight or dimension of these applications,...but does it really matter?

Yes, it really matters!!!

You say you are an artist (graphic designer). How much paint is required to paint a picture?

The answer is that it depends on the picture size and on how thick the paint is applied and how much of the picture area gets painted. Is the picture a billboard or a postcard? Are many colors used or only one? Do you use watercolors or oil paints?

It was a joke!

Because it's so obvious that size and weight matters (in these incidents you are free to pick any weight and size you prefer) ...but also, that we can all see how many horses (FORCE) we need for the applications to make them turn VERY slowly.

The point is the speed = RPM (TIME)

And here it's so obvious that you have all the parameters you ask for:

Dimension, Time, Weight, Force, Distance...

What more could you possibly demand?

regards
ruggero ;-)

[ruggerodk]

Jim:
I've looked at the link to BW calculation page.

Here are the specification next to my wheel (as italic):

Gera (1st) Wheel – (My Wheel)

Gera (1st) Wheel lifting weight... – (Whatever)

2.5 ell (4.65 ft) diameter wheel – (10 ft)

About 60 RPM or more – (40-50 RPM)

Unknown Axle size, assume 4 inches. – (Unknown)

Several pounds according to Wagner, assume 4 pounds. – (8 weights, 100 lbs each)

If it is possible to calculate a Bessler Wheel from these sparse specifications, the why on earth are people so persistantly rejecting to calculate from exactly the same sparse information for my wheel...?

Either the webpage is making false calculations out of the blue (because some specification are said missing), or .....somebody's stating a falsum.

regards
ruggero ‚-)

[jim_mich]

Gera (1st) Wheel lifting weight... – (Whatever)

Without knowing how much weight is being lifted we cannot calculate HP.

If it is possible to calculate a Bessler Wheel from these sparse specifications, the why on earth are people so persistantly rejecting to calculate from exactly the same sparse information for my wheel...?

Because your specifications are too sparse.

PS. I wrote that Wiki page.

[jim_mich]

And here it's so obvious that you have all the parameters you ask for:

Dimension, Time, Weight, Force, Distance...

What more could you possibly demand?

To calculate horsepower requires that you know three things: Force. Distance. Time.

What is the force? What is the Distance?

Are we talking about an out-of-balance (OOB) wheel? Then we need to know how much OOB the wheel is. This requires a conversion from weight force to torque. This conversion requires knowledge of where the weights are located inside the wheel and knowledge of when they shift from position to position. Without this knowledge then HP cannot be calculated.

[justsomeone]

Ruggero, I can answer your question. You say the input power is "x".

Then your HP rating of this ring (wheel) is...... "x" !!!!!

I hope this helps.

[ruggerodk]

Without knowing how much weight is being lifted we cannot calculate HP.

your specifications are too sparse.

Well Jim, I'm sorry to hear that.
But you didn't answer my question.
How do you explain the differences (if any) on the two sets of specification?
Can you tell us exactly how much weight is being - and how far -lifted in Besslers Gera wheel?
If you believe you can, please tell us how you came to that knowledge.

I made a quick search on wikipedia on Horsepower and guess what: It tell us a nice and very interesting story of HOW mr. Watt (himself) made the calculation for Horsepower.
Here it is...

"Watt determined that a horse could turn a mill wheel 144 times in an hour (or 2.4 times a minute)(i.e. RPM).
The wheel was 12 feet in radius, (Size) therefore the horse travelled 2.4 × 2π × 12 feet in one minute. (Distance)

Watt judged that the horse could pull with a force of 180 pounds (assuming that the measurements of mass were equivalent to measurements of force in pounds-force, which were not well-defined units at the time). So:

power = (work / time) = ((force x distance) / time) = (((180 lbf) x (2.4 x 2 pi x 12 ft)) / 1 min)) = 32,572 ((ft x lbf) / (min)).

This was rounded to an even 33,000 ft·lbf/min.

Others recount that Watt determined that a pony could lift an average 220 pounds 100 feet (30 m) per minute over a four-hour working shift. Watt then judged a horse was 50% more powerful than a pony and thus arrived at the 33,000 ft·lbf/min figure."

As we don't know the exact weight of mr. Watt's mill, I believe a math genius could easily solve that puzzle, knowing that the horse (according to mr. Watt) pull some 180 pounds.
In my opinion - still not a math genius - this 180 pounds represents a constant and not a variable.
If the pony could lift an average 220 pounds 100 feet (30 m) per minute Then the horse can lift an average 330 pounds 100 feet per minute.
I don't know if mr. Watt made a distingtion between LIFT and PULL...but anyway we have a measurement that equals a lift of 330 pounds 100 feet per minute to 180 pounds pull.


Several ask for a specification of force involved....Well, it should be obvious to everyone that it is...yes, gravity. What a surprise.

regards
ruggero ;-)

[jim_mich]

Can you tell us exactly how much weight is being - and how far -lifted in Bessler’s Gera wheel?
If you believe you can, please tell us how you came to that knowledge.

The specifications of Bessler's Gera wheel are the least known. Therefore logical assumptions must be made in order to calculate its HP. If you/we change the assumptions then the estimated HP will change. This is how things work when dealing with assumptions. But if the assumptions are correct then the minimum calculated HP is correct.

From the Wiki:

Gera (1st) Wheel lifting weight...

2.5 ell (4.65 ft) diameter wheel

About 60 RPM or more

Unknown Axle size, assume 4 inches.

Several pounds according to Wagner, assume 4 pounds.


V = (4/12) • 3.14159265359 • 60 / 60

V = 62.83185 Feet/Minute / 60

V = 1.047198 Feet/Second

HP = 4 • 1.047198 / 550

HP = 0.0076 Horse Power (about 1/132)

W = 5.68 Watts

The assumption for the Gera wheel axle was 4 inches. The assumption for the weight object was 4 pounds. Using a rope wrapped around a 4 inch axles rotating at 60 RPM produces a lifting speed of 62.83185 Feet/Minute. The weight was lifted up to a pulley attached under the roof outside the window. If this distance was 20 feet then it would have taken about 19 seconds. Again, assumption must be made because no one left us any writen record of exactly how long it took to lift the load or exactly how high the roof was.

If you can give me enough assumptions for your wheel then we can calculate its HP. I need to know how much weight your wheel will pull or lift (not how much it weighs).

My question, "What is the force?" was asking for the amount of force, not the source of the force. If gravity is the source of the force then we need to know the amount of weight involved (which you supplied) and we need to know how the weight force is applied. For example, is it applied at a radius of 4 feet on one side of your wheel and at 2 feet on the other side? Does it shift upward instantly at 12 o'clock and at 6 o'clock? From this we can calculate the distance that the weight force moves the weight objects.

If you can supply some assumptions then we can calculate the assumed HP. So far you have not supplied how much you wheel can pull or lift.

-------

The English language can sometimes be confusing. "Force" can mean a force value or it can mean a force source. "Weight" can mean a gravity force or it can mean an object. Usually the meaning can be deduced from the context, but sometime it is very confusing as to what is meant by the writer. Therefore it is up to the writer to attempt to make his meaning absolutely clear.