Does Heating Helium Increase Its Buoyancy?

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    Heating Helium
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Discussion Overview

The discussion revolves around the effects of heating helium and its potential to generate movement in a turbine, similar to steam engines. Participants explore the implications of using helium as a working fluid in energy generation and its buoyancy compared to other gases.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants propose that heating helium could generate movement due to increased molecular activity, while others express skepticism about its effectiveness compared to other gases.
  • There is a suggestion that helium behaves like other gases when heated, but its low density and molecular weight may influence its performance in turbines.
  • One participant mentions that heating gas causes it to expand, which could potentially turn turbines, but emphasizes that using water to create steam is a more established method.
  • Some participants question the rationale for using helium over cheaper alternatives like air or nitrogen, particularly in terms of cost and efficiency.
  • There is a discussion about the Brayton cycle and the use of helium in high-temperature gas-cooled nuclear reactors, indicating its potential applications in specific contexts.
  • Concerns are raised about the OP's belief that heating helium might increase its buoyancy, with some participants suggesting this notion may be misguided.
  • One participant notes that while helium is unreactive and does not burn, the challenges of containing it in a cooling circuit may complicate its use.

Areas of Agreement / Disagreement

Participants express a mix of agreement and disagreement regarding the effectiveness of heating helium for generating movement in turbines. Some believe it could work under certain conditions, while others argue that it may not be practical or efficient compared to other methods.

Contextual Notes

Participants highlight the need for a specific setup to effectively use heated gases for energy generation, and there are unresolved questions about the efficiency and practicality of using helium versus other gases.

ybhathena
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For example, if I had contained helium, and then I increased the temperature and installed spinners and motors inside would that move due to the activity produced by the high energy helium , or would the movement caused by the helium not be powerful enough to move the spinners. (I think it should because high temperatures cause the gas molecules to move very quickly and become extremely unstable)
 
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ybhathena said:
For example, if I had contained helium, and then I increased the temperature and installed spinners and motors inside would that move due to the activity produced by the high energy helium , or would the movement caused by the helium not be powerful enough to move the spinners. (I think it should because high temperatures cause the gas molecules to move very quickly and become extremely unstable)

Helium would act essentially like any other gas. I'm not sure what your setup is, or what these spinners and motors do.
 
What are these "spinners"?
 
LURCH said:
What are these "spinners"?
My guess is blades - for fans or turbines. But the OP seems to have some misconceptions about what the heated helium will do.
 
So basically I wanted to find a way to see if heating gas will generate movement and move a turbine to generate electricity, similar to how we heat water to create steam to generate electricity. I was basically wondering if the same could be done perhaps with a sensitive gas such as helium or any other for that matter.
 
ybhathena said:
So basically I wanted to find a way to see if heating gas will generate movement and move a turbine to generate electricity, similar to how we heat water to create steam to generate electricity. I was basically wondering if the same could be done perhaps with a sensitive gas such as helium or any other for that matter.
It will take more energy to heat the gas than you will gain from the turbines. This is a "free energy" design idea. Alas, it will not work.
 
But what if the heat is already excess and simply being wasted?
 
You can power a generator with heated helium with the right setup. However, why do you plan to use helium? Air is cheaper. If burning materials might be a problem, use nitrogen.
 
Oh ok, but what do you mean by burning materials and the use of nitrogen?
 
  • #10
Also if air is heated, is it sensitive enough to move the turbine and generate electricity? That is my main concern
 
  • #11
ybhathena said:
Also if air is heated, is it sensitive enough to move the turbine and generate electricity? That is my main concern

That is entirely up to your setup. It is certainly possible to heat up a gas and have it turn a turbine.

Though it would be more effective to start with liquid water and heat it to steam, which would cause it to expand many-fold.

The expansion of a gas is directly proportional to the heating (Charles' Law). so to double the volume, you'd have to double the temperature (that's absolute temp - Kelvins). i.e. to double the volume of a room temperature gas would require heating it to about 600K (~320C).
 
  • #12
Yes you can make an engine using helium as the working fluid. It would run on the Brayton cycle, similar to gas turbines and jet engines. Helium can and has been used for high temperature gas cooled nuclear reactors. To answer the topic title question, heating helium "does nothing", which is why it is useful for a coolant at high temperatures (i.e. it does not chemically react with materials nor does it absorb neutrons and become radioactive).
 
  • #13
QuantumPion said:
Yes you can make an engine using helium as the working fluid. It would run on the Brayton cycle, similar to gas turbines and jet engines. Helium can and has been used for high temperature gas cooled nuclear reactors. To answer the topic title question, heating helium "does nothing", which is why it is useful for a coolant at high temperatures (i.e. it does not chemically react with materials nor does it absorb neutrons and become radioactive).

But I imagine it is the very devil to contain in a cooling circuit.
 
  • #14
sophiecentaur said:
But I imagine it is the very devil to contain in a cooling circuit.

Main generators are cooled with hydrogen and they work just fine. I'm sure there are some losses due to leakage and diffusion but not so much that can't be accounted for by make-up.
 
  • #15
And I guess what does get out is harmless, wherever it's been.
 
  • #16
Heating helium will make hot helium. Helium is very unreactive, so you aren't going to burn the helium or anything like that. Heating gas causes it to expand, so you can use it to turn turbines if you desire. Is there any reason to use helium here, other than water? Steam turbines have existed for some time now.
 
  • #17
The OP has mentioned more than once his/her belief that helium is somehow sensitive or unstable when heated. It sounds like he/she is hoping that heating He will increase its buoyancy in air more than it might some other non-buoyant gas. Hopefully, he/she is realizing this is barking up the wrong turbine tree, yes?
 
  • #18
DaveC426913 said:
The OP has mentioned more than once his/her belief that helium is somehow sensitive or unstable when heated. It sounds like he/she is hoping that heating He will increase its buoyancy in air more than it might some other non-buoyant gas. Hopefully, he/she is realizing this is barking up the wrong turbine tree, yes?

I don't think so. At least not in this thread. The OP posted:

ybhathena said:
So basically I wanted to find a way to see if heating gas will generate movement and move a turbine to generate electricity, similar to how we heat water to create steam to generate electricity. I was basically wondering if the same could be done perhaps with a sensitive gas such as helium or any other for that matter.

I'm not exactly sure what she meant by "sensitive gas" but I took it to mean its low density and molecular weight. And she specifically mentioned "any other gas for that matter" so I'm pretty sure she is just wondering what the effect of using different fluids for a heat engine would be.
 

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