Air circulation question [Image attatched]

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    Air Circulation
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Discussion Overview

The discussion revolves around a theoretical question regarding air circulation in a closed system that includes both water and air at different pressures. Participants explore the implications of using a one-way valve to allow air to flow into the water and the potential for continuous circulation of air within the system.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Tom proposes a closed system where air at higher pressure is separated from water by a one-way valve, questioning whether this setup would allow for continuous air circulation.
  • Some participants argue that the pressure at the bottom of the water column would prevent gas from entering the liquid, suggesting that the system as described would not function as intended.
  • There is a suggestion that an air pump would be necessary to create a pressure differential that could allow for the desired circulation of air bubbles.
  • Tom expresses a desire to use the system to generate electrical energy through induced emf, indicating a goal of achieving this without consuming energy.
  • Participants emphasize that energy input is required to produce bubbles and that the system cannot operate without some form of work being done on it.
  • Tom argues that if the system is pressurized and a one-way valve is used, air circulation could be maintained, but others counter that it would only move once before stopping.
  • There is a mention of the concept of perpetual motion machines, with a warning that such discussions are against forum rules.

Areas of Agreement / Disagreement

Participants generally disagree on the feasibility of continuous air circulation in the proposed system. While some assert that it cannot work as described, others explore the idea of maintaining pressure and circulation, leading to an unresolved discussion.

Contextual Notes

Participants highlight the need for a pressure differential and the limitations of the proposed system design. There are unresolved assumptions regarding the behavior of gases and liquids under pressure in this context.

tliguori330
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Hello,

My name is Tom and I had a theoretical question about general air pressure and circulation. i have attached an image to diagram the system I am describing.

In this closed system loop there is one part of a loop filled with water and the other part filled with air at a higher pressure. They are separated by a one way valve that let's the air flow into the water only.

Will the air continually circulate around this system?

Thanks,
Tom
 

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    air pressure system.png
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Short answer - NO.

Longer answer - pressure at the bottom of the column of water ( from the gas pressure + mgh of the water ) is higher than the gas pressure at the value. No gas will enter the liquid. Why would you think that filling one side with a fluid of higher density ( so bubbles of gas could float to the surface ), would add anything to just having both sides liquid or both sides gas.
 
256bits said:
Short answer - NO.

Longer answer - pressure at the bottom of the column of water ( from the gas pressure + mgh of the water ) is higher than the gas pressure at the value. No gas will enter the liquid. Why would you think that filling one side with a fluid of higher density ( so bubbles of gas could float to the surface ), would add anything to just having both sides liquid or both sides gas.


The plan is to float something in the water side which will collect the bubbles to increase its buoyancy.
 
Well, that system will not be able to do that for you, as no bubbles will enter the water the way it is set up.
 
You will basically need an air pump to provide a pressure at the bottom of the water column that is greater than the hydrostatic pressure of the water. Whatever the "high pressure" in your diagram (as it is drawn), water will flow up that side tube until the two water levels are the same.
 
Let me know if this does not make sense but, the thought for the valve was that it would only allow air to flow into the water tank and not let water flow the other way. I am assuming that devices like that exist. maybe something similar to a squeeze ketchup/Gatorade bottle.
 
tliguori330 said:
Let me know if this does not make sense but, the thought for the valve was that it would only allow air to flow into the water tank and not let water flow the other way. I am assuming that devices like that exist. maybe something similar to a squeeze ketchup/Gatorade bottle.

However you achieve it, valves / squeezing etc., you need pump to produce a small excess pressure at the bottom of that column. Adding the same pressure to both sides will achieve nothing.
 
Can anyone think of a way to Keep the air pockets circulating? I want to catch them at the bottom of the water tank, float an object, then release the capture air, let the object sink and repeat.
 
Which bit about "air pump" that I suggested earlier is difficult to understand? Lol
 
  • #10
sophiecentaur said:
Which bit about "air pump" that I suggested earlier is difficult to understand? Lol


All right, take it easy there boss. I want to use this concept to produce electrical energy through induced emf using faraday's law. I don't want to consume energy to make it happen. Maybe a mechanical air pump just to pressurize the whole system.
 
  • #11
The point is that you won't get any energy out unless you put some (the same amount plus some) in. Basic rule of Physics / life / bank accounts. You will need to do work on the air to produce the bubbles which you could then play about with to produce electrical energy (if you are ingenious enough). You don't get owt for nowt, as they say in Yorkshire.
 
  • #12
The energy i plan on putting is pressure before closing the system. So hand pumping air into build pressure. If the system is pressurized and there is a one way stopper between the water and air i feel like the air would keep circulating.
 
  • #13
tliguori330 said:
The energy i plan on putting is pressure before closing the system. So hand pumping air into build pressure. If the system is pressurized and there us a one way stopper between the water and air i feel like the air would keep circulating.

It would move once and then stop. You can't beat the system.
 
  • #14
Why would it stop the pressure in the system would always be a high pressure i think. There would be no loss in pressure in the system overall, once the bubbles pass the valve the pressure would increase pushing more bubbles through the valve and so on.
 
  • #15
Thread is closed.

@tliguori330 -- Perpetual Motion Machines (PMMs) are on the list of Forbidden Topics in the PF Rules (see Site Info at the top of the page). You agreed to abide by those rules when you joined the PF. Please do not post about them again here.

From the Rules link:

PF Forbidden Topics said:
Pseudoscience, such as (but not limited to):

Perpetual motion and "free energy" discussions
http://wiki.4hv.org/index.php/Free_Energy_Debunking
http://en.wikipedia.org/wiki/Perpetual_motion
http://www.skepdic.com/freeenergy.html
http://www.skepdic.com/perpetual.html
 

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