Author Topic: Perpetual motion by capillary action  (Read 1570 times)

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Online Circlotron

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Perpetual motion by capillary action
« on: November 10, 2018, 09:33:35 am »
Tell me why this won't work.

Trees manage to raise water to a great height by capillary action.
Say we had some kind of wick to raise water up to a tank, then use the potential energy of that raised water to do some work on the way back down again. What is (presumably) wrong with this situation?
 

Offline Raj

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Re: Perpetual motion by capillary action
« Reply #1 on: November 10, 2018, 09:50:05 am »
you'll need energy to extract water out of the capillary. The Sun and the stored energy of tree itself,does that in trees.

Correct me if i'm wrong
« Last Edit: November 10, 2018, 09:52:25 am by Raj »
 
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Online ogden

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Re: Perpetual motion by capillary action
« Reply #2 on: November 10, 2018, 09:50:54 am »
Tell me why this won't work.

Trees manage to raise water to a great height by capillary action.
Say we had some kind of wick to raise water up to a tank, then use the potential energy of that raised water to do some work on the way back down again. What is (presumably) wrong with this situation?

Don't you know how to use internet search engines? Answer is all over the internet, including wikipedia:

it was thought that the capillary action would keep the water flowing in the tube, but since the cohesion force that draws the liquid up the tube in the first place holds the droplet from releasing into the bowl, the flow is not perpetual
 
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Offline CatalinaWOW

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Re: Perpetual motion by capillary action
« Reply #3 on: November 11, 2018, 02:04:41 am »
Since raising water seems to fascinate you, here is a workable, psuedo-perpetual machine.

Anchor a reverse osmosis filter in deep ocean water.  Run the output pipe up to the surface.  The pipe fills with fresh water which is less dense than salt water, so a pressure differential across the RO membrane is maintained sustaining the flow. 

You can extract energy from this flow.  It also provides a continual source of fresh water.

Doesn't violate any thermodynamic laws and the oceans are large enough that it would take a LONG, LONG time to run the fundamental source out.  I'll leave it as an exercise for the student to figure out why this isn't widely done.
 

Offline Raj

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Re: Perpetual motion by capillary action
« Reply #4 on: November 11, 2018, 09:16:24 am »
Since raising water seems to fascinate you, here is a workable, psuedo-perpetual machine.

Anchor a reverse osmosis filter in deep ocean water.  Run the output pipe up to the surface.  The pipe fills with fresh water which is less dense than salt water, so a pressure differential across the RO membrane is maintained sustaining the flow. 

You can extract energy from this flow.  It also provides a continual source of fresh water.

Doesn't violate any thermodynamic laws and the oceans are large enough that it would take a LONG, LONG time to run the fundamental source out.  I'll leave it as an exercise for the student to figure out why this isn't widely done.

Let me guess,...it isn't viable because,you won't be able to flush out the membrane,thus it gets blocked?
 

Offline Urs42

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Re: Perpetual motion by capillary action
« Reply #5 on: November 11, 2018, 11:20:51 am »
Look at the Hydraulic ram, but this is not a perpetual machine...

https://en.wikipedia.org/wiki/Hydraulic_ram
 

Offline CatalinaWOW

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Re: Perpetual motion by capillary action
« Reply #6 on: November 11, 2018, 02:13:32 pm »

Let me guess,...it isn't viable because,you won't be able to flush out the membrane,thus it gets blocked?

That is one reason, though there are ways to solve that   The cost/complexity of the solutions is on off the coffin nails.
 

Offline Max2018

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Re: Perpetual motion by capillary action
« Reply #7 on: December 05, 2018, 05:07:30 pm »
you'll need energy to extract water out of the capillary. The Sun and the stored energy of tree itself,does that in trees.

Correct me if i'm wrong

But it is working with liquid helium. Now we can beat all the laws of thermodynamic by just using helium and quantum physics.
 

Offline GregDunn

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Re: Perpetual motion by capillary action
« Reply #8 on: December 05, 2018, 07:13:28 pm »
you'll need energy to extract water out of the capillary. The Sun and the stored energy of tree itself,does that in trees.

Correct me if i'm wrong

But it is working with liquid helium. Now we can beat all the laws of thermodynamic by just using helium and quantum physics.

Neglecting, of course, the energy you have to expend to maintain the helium temperature near absolute zero.
 

Offline jmelson

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Re: Perpetual motion by capillary action
« Reply #9 on: December 05, 2018, 09:01:26 pm »

But it is working with liquid helium. Now we can beat all the laws of thermodynamic by just using helium and quantum physics.
At 4 degrees K a whole BUNCH of the laws of physics get bent, if not totally broken.  But, there is a limit to what you can do at these temperatures.  And, extracting ANY energy out of a system at 4 K is pretty much impossible (that's how you GET down to 4 K in the first place.)

Jon
 

Offline rcbaughn

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Re: Perpetual motion by capillary action
« Reply #10 on: December 06, 2018, 12:35:23 am »
The only viable water driven power system that requires no input power to get going is the use of long bendable tubes that create energy from the movement that the tide and waves provide. At least that is the only water driven way to collect energy that has popped up as of the last decade, dams and water wheels not considered.
 

Offline CatalinaWOW

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Re: Perpetual motion by capillary action
« Reply #11 on: December 06, 2018, 12:36:43 am »
The simplest, non-equation way I can think of to explain why you can't do perpetual motion with liquid helium is this.  Your conventional physics view of the helium behavior is that it has climbed to a higher point and you can consume the power from it flowing back down again (or being let down in a bucket).  But why would you expect it to flow down, or stay in the bucket after the behavior that got it up there in the first place?
 


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