The force and energy effect of a magnetic field on a conducting medium. Models and experiments
DOI:
https://doi.org/10.17072/1994-3598-2020-2-10-37Keywords:
constant magnetic field, traveling magnetic field, rotating magnetic field, alternating magnetic field, magnetohydrodynamics, eddy current, Lorentz force, induction heating, Hartmann number, magnetic field diffusion parameterAbstract
The review of the existing methods and technologies for influencing conductive media with magnetic fields, which can be applied in principle in three ways: constant, running (and rotating as its variant) and alternating (harmonically changing) is presented. The general equations of electromagnetism for a moving conducting medium are analyzed, and dimensionless criteria that are important for the description are given. Mathematical models are considered for each type of magnetic field application, and the model equations are written in as much detail as is sufficient to calculate the corresponding impact. For each type of field, data from full-scale and computational experiments are provided. The main attention is paid to the alternating magnetic field, the other types are presented more briefly, but enough to start moving in the appropriate direction. In conclusion, the list of the works that are useful for verifying mathematical models is given. For the convenience of working with English-language search and science databases, the English version is provided for the most important terms.References
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