Charged liquid jet instability

AI Thread Summary
The discussion centers on the instability of an infinitely long charged liquid jet, particularly focusing on how changes in the surface profile affect surface charge density and electric energy. The electric energy change of the liquid jet is denoted as E, while the energy change in the connected charging system is -2E. The original paper referenced does not provide a proof for this result, prompting the inquiry for a theorem that could explain it. A participant shares a resource that may help address the problem. The complexity of the issue is acknowledged, indicating the need for further exploration.
weiwei
I am dealing with a problem of instability of an infinitely long charged liquid jet. When there is a change is surface profile(which originally is a column with radius R), it surface charge density changes, thus the electric energy change of the liquid jet is E (due to surface charge density change), the charging system (a constant voltage V connected to the liquid jet) has energy change -2E, the paper I am reading just gives this result without proving it. So I am trying my luck here to see if any theorem can explain it.
 
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weiwei said:
I am dealing with a problem of instability of an infinitely long charged liquid jet. When there is a change is surface profile(which originally is a column with radius R), it surface charge density changes, thus the electric energy change of the liquid jet is E (due to surface charge density change), the charging system (a constant voltage V connected to the liquid jet) has energy change -2E, the paper I am reading just gives this result without proving it. So I am trying my luck here to see if any theorem can explain it.

Zoiks! This is a tough problem. I found this:

https://web.duke.edu/uphyl/pubs/Chen_11_Springer_EHD_Stability.pdf

It seems to discuss your problem. Good luck!
 
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