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Here is a some what simple design that would have the potential of working.

The numbers. The left static head can be 11 inches. The one on the right can be 12 inches. The tube on the left can be 3/4 inch in diameter and the one on the right, 1/2 inch in diameter. The discharge static head is at the same level as the water in the top reservoir.

This means the inlet would be slightly above it. The trick with this is getting the vacuum in the top reservoir and priming both static heads.

The volume of the left static head would be a little more than twice that of the one on the right. That should be able to effect the vacuum enough to establish the proper flow. If anyone wants to check the math, it is as follows;

Pi times radius squared times height equals volume

3.142 x.25 x .25 x 12 = 2.35, that's for the static head on the right. And the one on the left is

3.142 x 375 x .375 .11 = 4.86

What is seen by doing some math, the inlet tube has 2.35 cubic inches and the discharge tube has 4.86 cubic inches of water. Why would I think this could work ? Because the static head on the left would increase the vacuum. When this happens, the right side having less mass would be drawn into the vacuum. As this happens, the static head on the left is replenished. It's discharge rate would be the same as the water from the inlet flowing into the reservoir, automatic flow control !

And by the way, trying something like this can be done for around $20. Plastic is inexpensive and fairly easy to work with. Showing the static heads. The water between the lines is what matters. The other water helps to create seals, you know, prevent air from entering the system and of course, maintain flow.

post-10545-073145700 1282488258_thumb.jpg

 

edited to correct spelling

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It would mean more to people if they took the time to do the math themselves.

I’m certain this perpetual motion machine won’t work.   I think I see a simple physics mistake that caused you to think it might, Jim. Though one would intuitively think, as you do, that the pressure

The height in both would be equal. I think Craig did well explaining why.   To find the height divide the pressure inside the container (at the top) by the pressure outside. Subtract that result fro

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Here is a some what simple design that would have the potential of working.

The numbers. The left static head can be 11 inches. The one on the right can be 12 inches. The tube on the left can be 3/4 inch in diameter and the one on the right, 1/2 inch in diameter. The discharge static head is at the same level as the water in the top reservoir.

This means the inlet would be slightly above it. The trick with this is getting the vacuum in the top reservoir and priming both static heads.

The volume of the left static head would be a little more than twice that of the one on the right. That should be able to effect the vacuum enough to establish the proper flow. If anyone wants to check the math, it is as follows;

Pi times radius squared times height equals volume

3.142 x.25 x .25 x 12 = 2.35, that's for the static head on the right. And the one on the left is

3.142 x 375 x .375 .11 = 4.86

What is seen by doing some math, the inlet tube has 2.35 cubic inches and the discharge tube has 4.86 cubic inches of water. Why would I think this could work ? Because the static head on the left would increase the vacuum. When this happens, the right side having less mass would be drawn into the vacuum. As this happens, the static head on the left is replenished. It's discharge rate would be the same as the water from the inlet flowing into the reservoir, automatic flow control !

And by the way, trying something like this can be done for around $20. Plastic is inexpensive and fairly easy to work with. Showing the static heads. The water between the lines is what matters. The other water helps to create seals, you know, prevent air from entering the system and of course, maintain flow.

post-10545-073145700 1282488258_thumb.jpg

 

edited to correct spelling

 

 

I use siphons nearly every day, they are a cheap and easy way to transfer fluids from a high place to a low place. I'm not sure what you are suggesting, are you saying a siphon can transfer fluids in a circular manner? please clarify

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Here is a some what simple design that would have the potential of working.

I’m certain this perpetual motion machine won’t work.

 

I think I see a simple physics mistake that caused you to think it might, Jim.

Why would I think this could work ? Because the static head on the left would increase the vacuum. When this happens, the right side having less mass would be drawn into the vacuum. As this happens, the static head on the left is replenished. It's discharge rate would be the same as the water from the inlet flowing into the reservoir, automatic flow control !

Though one would intuitively think, as you do, that the pressure exerted by a column of fluid is proportional to its volume, it’s not. It’s proportional only to the height of the column of water. This hyperphysics page has a good illustration of this, but it’s one of those counterintuitive things you really must see to believe – my 7th grade science classroom had a nifty demo gadget with different diameter clear cylinders with sealable nozzles at different heights, but a quick experiment you can do if you have, say, a garden hose (or better, some wide clear tubing), some (narrow) aquarium tubing, and a bucket, is to note that if you fill the hose and the tubing, then put one end of each in the bucket, and raise the other ends, the water will settle at the same height in both tubes.

 

So, your key assumption that the larger volume tube on the left would draw fluid from the upper vessel, while the smaller volume one on the right would draw fluid into it, is false. What would happen is that the fluid in the right column would fall until the same height as the one on the left, as shown in my slight edit of your picture below.

post-1347-004869000 1283296817_thumb.jpg

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Welcome to our science forums! You should try it and post some pictures. :mellow:

Thanks.

I'm not sure when I will be able to. I have looked at what is available material wise.

I have been trying to find clear plastic tubing. Then if it were to work, it could be seen how.

 

@moontman, Yep, it would be a "circular motion. What might be confusing is the discharge could drain into the same reservoir as the inlet.

Why this would not matter (see capillary behavior) is because the bottom reservoir would be exposed to the atmosphere.

 

@hummingbird, I hadn't thought of that. As the drawing shows, the discharge could be to a raised reservoir.

Perfect for pets or animals to drink clean water from.

 

@All, while the vacuum in the top reservoir would act on both colums of water, the column with more water should pull on the vacuum more.

And it would be this shifting of the space the vaccum takes up that would help to create a directional flow of water if possible.

I have thought of a simple way this might be tested.

If both tubes are in the same reservoir, then another tube attached to the top reservoir could be used to suck out the air and fill the 2 other tubes and reservoir with water.

The inlet tube should fill first as it would hold less water. If so, then once the inlet tube is filled, the opening in the water could be temporarily plugged with your finger.

Then by increasing the vacuum in the resrvoir, the discharge tube would fill. And when water levels are okay, then you can remove your finger from the inlet.

And hpefully, there would be a flow of water.

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I have been trying to find clear plastic tubing.

Go to an auto parts store and look for clear PVC fuel line. It can usually be had in 3/32” to 3/8” inside diameters in any length you want, for well under US$1/foot.

 

Get a tube or two of clear silicone sealant from a hardware/home improvement store (usually the bathroom/plumbing section).

 

You should be able to drill and silicone together clear plastic drinking glasses or something similar, insert and silicone in place your tubes, to build a good-size model of your sketch, for under $25.

 

However, as I noted in post #6, it’s as certain as the laws of physics can be that the device will not endlessly circulate water (or any other fluid), but will settle into 2 columns of fluid of the same height.

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The volume of the left static head would be a little more than twice that of the one on the right. That should be able to effect the vacuum enough to establish the proper flow.

 

The height in both would be equal. I think Craig did well explaining why.

 

To find the height divide the pressure inside the container (at the top) by the pressure outside. Subtract that result from one then multiply by 34 feet. To convince yourself that the size of the tubing doesn't affect the height consider a mercury barometer:

 

 

the height of mercury will be roughly 30 inches regardless of the width of the barometer's tube. The pressure that the fluid exerts is not dependent on the fluid's volume or mass. It depends only on the fluid's density, height, and the force of gravity. The page Craig gave explains quite well: Static Fluid Pressure

 

~modest

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@All, while the vacuum in the top reservoir would act on both colums of water, the column with more water should pull on the vacuum more.

 

It may seem so but that's incorrect. See the equations for hydraulic head. You'll see that the diameter of the vessel is not one of the variables in the equation. Head depends on height/depth only, not volume.

 

BTW, you could get some clear tubing at a pet supply house that has aquarium supplies.

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@All,

I am aware of static heads. Have both schooling and work experience.

The only reason the 2 columns would be the same height is if they are connected by a tube.

Then it would be capillary behavior. By having independent behavior in both static heads, the possibility does exist that it could work.

The reason why it would be possible is that the vacuum in the top rewervoir would act like a balancing lever, And the column with the greatest mass should have the greater influence on the vacuum.

This is something I do not believe has been tried before. But to use flexible tubing and a make shift set up might not give accurate results.

Such set ups might allow for leakage, etc. it could be that when I do it, I would like it to look like I paid attention to detail and thought it was worth trying in a respectable way.

What I will probably do is find out how much a glass set up would cost. Someone that is good with glass would have no problem making it.

And all it would need is one connection for a vacuum pump / gauge to be connected to it. If nothing else, it might make a nice conversation piece.

On the other hand, if it works, it would be worth showing to people.

Not sure when I'll be able to do it but will find out about costs.

 

 

 

Jim

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This is something I do not believe has been tried before.

I'm amazed how many time most perpetual motion machine ideas have been discussed and tried, so before concluding an idea about one is new, think you’d do well to at least browse a search engine (eg: Google) with some of its key words. For example, the 7th Google find on the phrase “self siphoning” (without quotes) finds this overunity.com forum thread, which discusses several variations of the theme, including some that appear at a glance much like your drawings.

 

There’s been hardly any credible scientific inquiry into “perpetual motion machines of the first king” for about 200 years, at the late 18th around the time most of the then major science societies stopped allowing them to be presented through their meeting and publications, arguably marking the point at which perpetual motion became fringe/pseudo-science.

 

Wikipedia’s history of perpetual motion machines has a good synopsis of the long history of the search for perpetual motion of various kinds, as do many other internet sites.

 

But to use flexible tubing and a make shift set up might not give accurate results.

Such set ups might allow for leakage, etc. it could be that when I do it, I would like it to look like I paid attention to detail and thought it was worth trying in a respectable way.

I still encourage you to try silicone seal, clear plastic ware and fuel tubing, as you could finish it quickly at very little cost and almost no risk of cuts or burns (just remember to wear plastic gloves and wash any stray silicone seal off your skin – it can give you a minor itchy rash).

 

Outside of fringe science societies like overunity, I’d not expect any credulous work on perpetual motion to garner any respectability. From a mainstream science perspective, its value is impressing on students that rigorous application of theory is better than primarily intuitive conclusions – in short, that conservation of energy really applies to the physical universe – and that it never hurts to experiment, even when the experiment is almost certain to fail to confirm the hypothesis, as is the case with perpetual motion hypothesis.

 

What I will probably do is find out how much a glass set up would cost. Someone that is good with glass would have no problem making it.

Good quality low-melting point (eg: flint) glass tube typically sells for about US$10 per pound. If you’re good a finding and scrounging through trash, it can be had for free.

 

Non-art glass blowing is easy to learn, and requires only a little equipment – a how-to kit can be bought online or at most science supply stores for around $100. Like a lot of students, I learned it in freshman (13th grade) introductory chemistry class.

 

If you’d rather have a pro make your glassware, craft fairs seem to me good places to find glassblowers – and fun places to visit just for aesthetics and entertainment.

 

Whatever approach you pursue, good luck, and post pictures! :)

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I'm amazed how many time most perpetual motion machine ideas have been discussed and tried, so before concluding an idea about one is new, think you’d do well to at least browse a search engine (eg: Google) with some of its key words. For example, the 7th Google find on the phrase “self siphoning” (without quotes) finds this overunity.com forum thread, which discusses several variations of the theme, including some that appear at a glance much like your drawings.

 

There’s been hardly any credible scientific inquiry into “perpetual motion machines of the first king” for about 200 years, at the late 18th around the time most of the then major science societies stopped allowing them to be presented through their meeting and publications, arguably marking the point at which perpetual motion became fringe/pseudo-science.

 

Wikipedia’s history of perpetual motion machines has a good synopsis of the long history of the search for perpetual motion of various kinds, as do many other internet sites.

 

 

I still encourage you to try silicone seal, clear plastic ware and fuel tubing, as you could finish it quickly at very little cost and almost no risk of cuts or burns (just remember to wear plastic gloves and wash any stray silicone seal off your skin – it can give you a minor itchy rash).

 

Outside of fringe science societies like overunity, I’d not expect any credulous work on perpetual motion to garner any respectability. From a mainstream science perspective, its value is impressing on students that rigorous application of theory is better than primarily intuitive conclusions – in short, that conservation of energy really applies to the physical universe – and that it never hurts to experiment, even when the experiment is almost certain to fail to confirm the hypothesis, as is the case with perpetual motion hypothesis.

 

 

Good quality low-melting point (eg: flint) glass tube typically sells for about US$10 per pound. If you’re good a finding and scrounging through trash, it can be had for free.

 

Non-art glass blowing is easy to learn, and requires only a little equipment – a how-to kit can be bought online or at most science supply stores for around $100. Like a lot of students, I learned it in freshman (13th grade) introductory chemistry class.

 

If you’d rather have a pro make your glassware, craft fairs seem to me good places to find glassblowers – and fun places to visit just for aesthetics and entertainment.

 

Whatever approach you pursue, good luck, and post pictures! :)

 

 

Craig,

Someone pointed out to me that someone tried a variation of this a long time ago.

As one person mis-stated, volume has everything to do with the static head. This would include the diameter of the pipe or tube.

This idea is based on what I learned in Propulsion Engineering School and what I worked with in an enginerrom. Such as vacuum being used to increase the potential that 900+ degree super heated steam @1200 psi, like that would need any help. As it turns out, even something like the boiler feeding the turbine which was rated at about 12,000 horse power could in fact use some help to be more efficient.

I think when schooling and practical experience are considered, then those things which effect the system can be taken into consideration.

What I think is almost funny is if something like this were to work, it would debunk one mainstream belief in science and outside of that, be be of no real practical value.

As things are, I do have something I am working on that I find more interesting.

 

 

Jim

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As one person mis-stated, volume has everything to do with the static head. This would include the diameter of the pipe or tube.

 

You might want to contact the engineers over at the Engineering Toolbox and educate them then because all of their equations are also missing a variable for volume. Perhaps you could share your equation for static head with us here so we can learn something. I've checked the references I have on hand and none of them list any equations with a variable for volume or pipe size either.

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What I think is almost funny is if something like this were to work, it would debunk one mainstream belief in science and outside of that, be be of no real practical value.

 

Falling water can turn a generator and make electrical power. If your idea worked as you describe it then anyone with such a device would have a perpetual source of free energy. The energy crisis would be solved because there would be no need for fossil or nuclear fuel. It would probably be the most significant and world-changing discovery in human history.

 

As one person mis-stated, volume has everything to do with the static head. This would include the diameter of the pipe or tube.

 

It could help to read the links people are posting. Craig's link states,

 

The pressure from the weight of a column of liquid of area A and height h is,

The most remarkable thing about this expression is what it does not include. The fluid pressure at a given depth does not depend upon the total mass or total volume of the liquid. The above pressure expression is easy to see for the straight, unobstructed column, but not obvious for the cases of different geometry which are shown.

 

and C1ay's:

 

For fluids - liquids or gases - at rest the pressure gradient in the vertical direction depends only on the specific weight of the fluid.

 

~modest

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Falling water can turn a generator and make electrical power. If your idea worked as you describe it then anyone with such a device would have a perpetual source of free energy. The energy crisis would be solved because there would be no need for fossil or nuclear fuel. It would probably be the most significant and world-changing discovery in human history.

 

 

 

It could help to read the links people are posting. Craig's link states,

 

 

 

and C1ay's:

 

 

 

~modest

 

Modest,

at best, I think it is something people would find interesting for a while. Then like all fads, it would pass.

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