Induction Magnetic Equation
Posted: 09 Sep 2021, 18:10
Hi,
I have a theoric question this time. By reading the Elmer models manual, I don't understand how the superposition between the induced magnetic field B^i and the external magnetic field B^e appears in the induced magnetic equation
Indeed, according to Faraday’s law of induction, the relative movement of a conducting fluid and a magnetic field causes an electromotive force (EMF) (of order |U × B|) to arise. Electrical currents will flow in general, with a current density
While, according to Ampere’s rule, these induced currents must produce a second, induced magnetic field. This adds to the initial magnetic field, and the change is generally sufficient that the magnetic field lines appear to be dragged along with the fluid:
The total magnetic field (imposed and induced) interacts with the induced current density, J, to produce a Lorentz force of J × B per unit volume. This has an effect on the conductor and is usually addressed at it.
Thanks in advance for your help,
Regards,
Andrea
I have a theoric question this time. By reading the Elmer models manual, I don't understand how the superposition between the induced magnetic field B^i and the external magnetic field B^e appears in the induced magnetic equation
Code: Select all
B=B^i+B^e
Code: Select all
J = sigma_m(U × B^e)
While, according to Ampere’s rule, these induced currents must produce a second, induced magnetic field. This adds to the initial magnetic field, and the change is generally sufficient that the magnetic field lines appear to be dragged along with the fluid:
Code: Select all
nabla × B^i = μJ
Thanks in advance for your help,
Regards,
Andrea