Undergrad Molten metal flow due to high currents

[avicenna]

It is mentioned in the book "Ampere-Neumann Electrodynamics of Metals", Peter Graneau, that Carl Hering in 1923 operated furnaces by passing high current through the molten metal pool. He observed molten metal flow due to the currents. How is the conductor motion explained?

 

[berkeman]

It is mentioned in the book "Ampere-Neumann Electrodynamics of Metals", Peter Graneau, that Carl Hering in 1923 operated furnaces by passing high current through the molten metal pool. He observed molten metal flow due to the currents. How is the conductor motion explained?

Since you haven't received any replies yet, I can ask if you are familiar with the basic equations for the forces between two parallel wires carrying equal currents. At a basic level, this would be one of the effects driving molten metal flows in the pool. There are several other secondary effects that would cause non-uniform flows as well...

http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/wirfor.html

 

[avicenna]

Since you haven't received any replies yet, I can ask if you are familiar with the basic equations for the forces between two parallel wires carrying equal currents. At a basic level, this would be one of the effects driving molten metal flows in the pool. There are several other secondary effects that would cause non-uniform flows as well...

View attachment 301526
http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/wirfor.html

I am not sure if the Pinch effect would cause molten metal flow. In Graneaus' experiment with a narrow trench of mercury, no visible pinch was observed - a pinch effect should cause a depression at the center of the mercury column.

 

[avicenna]

Since you haven't received any replies yet, I can ask if you are familiar with the basic equations for the forces between two parallel wires carrying equal currents. At a basic level, this would be one of the effects driving molten metal flows in the pool. There are several other secondary effects that would cause non-uniform flows as well...

View attachment 301526
http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/wirfor.html

Furthermore, the pinch effect is a transverse force. Flow of metal requires a force in line with the flow of metal.

 

[berkeman]

He observed molten metal flow due to the currents. How is the conductor motion explained?

I don't have access to the book. Is there something that describes the motion of the molten metal with respect to the electrical current flow? I'm assuming that the electrical current was DC and not AC?

 

[avicenna]

I don't have access to the book. Is there something that describes the motion of the molten metal with respect to the electrical current flow? I'm assuming that the electrical current was DC and not AC?

You can google : "Ampere-Neumann Electrodynamics of Metals"
Peter Graneau
Hadronic press.

Free pdf download available.

All these molten metal flow experiments are independent of direction of current. It works the same with AC currents. A typical example described in the above book is the Graneau's mercury fountain experiment.

 

[berkeman]

You can google : "Ampere-Neumann Electrodynamics of Metals"
Peter Graneau
Hadronic press.

Free pdf download available.

All these molten metal flow experiments are independent of direction of current. It works the same with AC currents. A typical example described in the above book is the Graneau's mercury fountain experiment.

There appear to be copyright violation issues with trying to find a PDF of that book. I've asked for help from the Science Advisors to try to find a legal copy of the book that we can access.

In the mean time, if you have the book, can you upload a single page scan of the pattern? That should be allowed under the Fair Use Copyright laws.

I've also searched on Graneau's mercury fountain experiment as you mentioned; is this what you are referring to?

https://dflund.se/~snorkelf/Longitudinal/node3.html

 

[avicenna]

The download link is here. I successfully downloaded a copy. Don't know if legal.

[Mentor Note -- It is not. The copyright is current, link is deleted...]

 

[DaveE]

Honestly, the physics is beyond me. However, I strongly suspect this is essentially the same/similar to the motion of ions in a plasma discharge. That may be a good approach for searching, since it's a much more common situation. I've seen a few links with lots of classical physics analysing what happens in plasmas. I'm sure you can find them too.

I worked for many years at a company that perfected high power ion lasers. The "pumping"* of gas ions in the plasma towards the cathode in the plasma tube was a significant issue for optimization. The tubes were designed with a gas "bypass" path outside (radially) from the main arc to allow for circulation. The high current region would move ions toward the cathode, the gas pressure would push them back around the outside of the arc towards the anode.

*No, not that kind of pumping. I meant physical transport, not atomic excitation. In the gas laser business "pumping" has two entirely different meanings, which is really unfortunate since they both refer to what's happening in the plasma gain medium.

 

[avicenna]

The download link is here. I successfully downloaded a copy. Don't know if legal.

[Mentor Note -- It is not. The copyright is current, link is deleted...]

What I did was a google search. We common people browsing the internet has no way to determine if a link given to us is legal or not legal. If moderators have way to know, of course they have all the rights to delete the links.

You could even ban me from this forum. But what can I say. There is no warning in the internet when we are given a link to download articles.

 

[Orodruin]

What I did was a google search. We common people browsing the internet has no way to determine if a link given to us is legal or not legal. If moderators have way to know, of course they have all the rights to delete the links.

You could even ban me from this forum. But what can I say. There is no warning in the internet when we are given a link to download articles.

It is still up to you to ensure legality. There is also no warning sign in the subway saying ”pickpocketing illegal”. If you are searching for books with the addition ”free download” then it is highly probable that at least a substantial part of your valid hits will be copyright infringements.

In this case, with the book less than 30 years old, you should at least search to see whether copyright has been released. If you cannot find information regarding this, it is very probable that it has not been.