Heat Transfer Machine

[Stevee]

As a discaimer, I realize that this theoratical device is both highly inefficient and is an engineering nightmare, still, I'm curious as to whether

- it could, theoratically, work as intended, and if so,

- is there anything like it in existence/has it been tried.

Please exuse my english.

From what I know (Which is not much, hence why I came here to discuss this), gases on a molecular level behave like small ping-pong balls, bouncing around all the time:

http://lab.concord.org/embeddable.html#interactives/sam/phase-change/2-two-types-of-gases.json

On large scale, the force inflicted on a sufrace by gas (In a peaceful environment) is more or less constant (the law of big numbers?). But what if we only have minimal quantities of gas molecules in a container? On a small time scale with highly sensitive equipment, we should be able to measure some fluctuation of pressure (Correct?). This fluctuation should also be present when dealing with larger quantitie of gas, but is insignificant compared to the average pressure.

Here is where the machine comes in:

http://i.imgur.com/pUtAhFE.png

A box with pockets of air inside, separated by airtight metal plates. The minimal fluctuation in pressurse should slightly push and pull the plates back and fourth, this movement could then be converted to electricity, which could be used to say, heat another boxfull of air. If I understand correctly, the temperature inside the machine's box would become cooler as a result of the energy extraction. The end result would be that without use of an external force/influence, heat gets transferred from one box to another.

Now I didn't go into any calculations yet, but fluctuation in pressure for each plate is probably way too small to make a real difference. Still, I would expect there to be at least a bare minimum of heat transfer taking place and that perhaps by improving it's design (Nano-tech would come in handy (Would we have to worry about the Casimir effect?)), the machine could become more efficient.

So, what are your thoughts? Is there anything important I left out? Is this idea worth pursuing or is it unfeasible? Perhaps its already somehow used and I just don't know about it?

[J.C.MacSwell]

 

As a discaimer, I realize that this theoratical device is both highly inefficient and is an engineering nightmare, still, I'm curious as to whether

- it could, theoratically, work as intended, and if so,

- is there anything like it in existence/has it been tried.

Please exuse my english.

From what I know (Which is not much, hence why I came here to discuss this), gases on a molecular level behave like small ping-pong balls, bouncing around all the time:

http://lab.concord.org/embeddable.html#interactives/sam/phase-change/2-two-types-of-gases.json

On large scale, the force inflicted on a sufrace by gas (In a peaceful environment) is more or less constant (the law of big numbers?). But what if we only have minimal quantities of gas molecules in a container? On a small time scale with highly sensitive equipment, we should be able to measure some fluctuation of pressure (Correct?). This fluctuation should also be present when dealing with larger quantitie of gas, but is insignificant compared to the average pressure.

Here is where the machine comes in:

http://i.imgur.com/pUtAhFE.png

A box with pockets of air inside, separated by airtight metal plates. The minimal fluctuation in pressurse should slightly push and pull the plates back and fourth, this movement could then be converted to electricity, which could be used to say, heat another boxfull of air. If I understand correctly, the temperature inside the machine's box would become cooler as a result of the energy extraction. The end result would be that without use of an external force/influence, heat gets transferred from one box to another.

Now I didn't go into any calculations yet, but fluctuation in pressure for each plate is probably way too small to make a real difference. Still, I would expect there to be at least a bare minimum of heat transfer taking place and that perhaps by improving it's design (Nano-tech would come in handy (Would we have to worry about the Casimir effect?)), the machine could become more efficient.

So, what are your thoughts? Is there anything important I left out? Is this idea worth pursuing or is it unfeasible? Perhaps its already somehow used and I just don't know about it?

 

Sounds similar in objective to a Maxwell's Demon or Brownian Ratchet, trying to beat the second law of thermodynamics...

 

https://en.wikipedia.org/wiki/Maxwell%27s_demon

 

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

Edited February 27, 2016 by J.C.MacSwell

[Stevee]

I see. Interesting. So they already tried many things.

 

Although, One thing I don't understand about the Brownian ratched.

 

"Although at first sight the Brownian ratchet seems to extract useful work from Brownian motion, Feynman demonstrated that if the entire device is at the same temperature, the ratchet will not rotate continuously in one direction but will move randomly back and forth, and therefore will not produce any useful work."

 

Random motion can be used to generate alternating electric current, no?

[J.C.MacSwell]

I see. Interesting. So they already tried many things.

 

Although, One thing I don't understand about the Brownian ratched.

 

"Although at first sight the Brownian ratchet seems to extract useful work from Brownian motion, Feynman demonstrated that if the entire device is at the same temperature, the ratchet will not rotate continuously in one direction but will move randomly back and forth, and therefore will not produce any useful work."

 

Random motion can be used to generate alternating electric current, no?

Essentially Feynman showed that, at the same temperature throughout, the mechanism is as at least as likely to slip as it is to consolidate a gain in potential energy.

 

It can be hard to pick out the flaws, but generally every scheme that tries to beat the second law of thermodynamics to produce useful energy at a macroscopic level can be shown why it won't work...and of course no one has ever built a mechanism of that type that works

[Stevee]

Hmmm... well, the heat transfer could be inefficient due to friction, resistance and whatnot, would it still violate the the 2nd law of thermodynamics if only a portion of the energy would get transferred while the rest gets transformed or leaves the system?

[Enthalpy]

What I do agree with:

• Impacts from molecules create a small force, momentum, etc
• This force fluctuates
• Some converter, for instance piezo, can make electricity of the fluctuation

This is confirmed by pressure sensors and microphones. They deliver an electric noise which, if their conversion is efficient like a piezo crystal is, results from the random movements of air molecules. Measurable and measured.

 

Where I disagree:

 

This movement converted to electricity won't heat a connected resistor beyond the gas' temperature.

 

The temperature equilibrium results from the electric power (called thermal noise) produced by the resistor too. The converter (piezo crystal) produces a mechanical noise from it and transfers it to the gas that gets heated too.

 

---------

 

This is a general, interesting and useful idea - though quite difficult to use - that results from thermodynamics' second law.

 

In the case of a piezo crystal used in the experiment you propose, it implies that the material is as "efficient" in converting work to electricity and electricity to work.

 

It wouldn't be so with a piezoresistive material for instance, which doesn't produce electricity from sound but only modulates the electric power available from a separate source. On such a microphone, you can put electric noise, but it produces no acoustic noise, because it's not a converter.