Is the Joule-Kelvin Expansion Reversible?

AI Thread Summary
The Joule-Kelvin expansion, also known as the Joule-Thompson effect, involves the free expansion of gas through a throttle valve. This process is quasistatic but is not reversible due to the necessity of a finite pressure difference across the throttle valve. The expansion relies on the presence of attractive forces between gas molecules, which is essential for the cooling effect to occur. Since throttling inherently involves irreversibility, the Joule-Kelvin expansion cannot be considered a reversible process. Thus, the conclusion is that the Joule-Kelvin expansion is not reversible.
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Homework Statement



Is the Joule Kelvin expansion reversible or not?



Homework Equations





The Attempt at a Solution



It\'s definitely quasistatic but I\'m not sure if it is reversible or not? I have a feeling it\'s not but can;t explain why...any ideas?
 
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bon said:

Homework Statement



Is the Joule Kelvin expansion reversible or not?

...

It\'s definitely quasistatic but I\'m not sure if it is reversible or not? I have a feeling it\'s not but can;t explain why...any ideas?
The Joule Kelvin or Joule-Thompson cooling effect requires letting the gas expand freely using a throttle valve. (It only works with gases having attractive forces between molecules.). Throttling is not a reversible process since it requires more than an infinitessimal pressure difference between the two sides of the throttle valve.

AM
 

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