Does Heating Helium Increase Its Buoyancy?

In summary: 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.And I guess what does get out is harmless, wherever it's been.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.
  • #1
ybhathena
42
0
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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  • #2
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.
 
  • #3
What are these "spinners"?
 
  • #4
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.
 
  • #5
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.
 
  • #6
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.
 
  • #7
But what if the heat is already excess and simply being wasted?
 
  • #8
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.
 
  • #9
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.
 

1. What happens to helium when it is heated?

When helium is heated, its atoms gain energy and move faster, causing the gas to expand. This expansion leads to a decrease in density and an increase in pressure.

2. Does heating helium change its properties?

Yes, heating helium changes its physical properties. It becomes less dense and more reactive at higher temperatures.

3. What is the purpose of heating helium?

Heating helium can be used to increase its pressure and volume, making it easier to store and transport. It can also be used in various industrial processes that require high temperatures.

4. Can heating helium cause it to turn into a different element?

No, heating helium does not cause it to turn into a different element. It will still remain as helium even at high temperatures.

5. Is it safe to heat helium?

Yes, it is generally safe to heat helium. However, precautions should be taken as with any gas under pressure. Helium can become flammable at high temperatures, so proper safety measures should be followed.

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