91292 - Electromagnetism and Magnetofluid-dynamics M

Learning outcomes

The course aims to deepen the study of electromagnetism, with reference to electrostatics, the quasi-stationary and non-stationary regime, of interest for electrical engineering. Then the interaction between electrodynamics and fluid-dynamics is analyzed. The motion of charged particles and ionized gases in the electromagnetic field is examined. The diffusive, convective and convective-diffusive magneto-fluid-dynamic regimes are considered. We will then examine the engineering aspects of the magnetofluidodynamic interaction with supersonic and hypersonic flows, the EHD interaction, and the controlled magnetic confinement thermonuclear fusion engineering.

Course contents

The course aims to deepen the study of electromagnetism and provide knowledge of some basic phenomena. Thereafter is dedicated to the study of the motion of charged particles and ionized gases in electromagnetic and fluid-dynamic fields.

The program of the course considers the following points:

• Insights into electrostatics
• Linked magnetic fluxes and electromagnetic induction
• Calculation of the ponderomotive forces
• Discontinuity of the electromagnetic fields
• Poynting's theorem
• Delayed potentials
• Quasi-stationary approximation
• Diffusion equation
• Skin effect in sinusoidal regimes
• Wave equations
• Electromagnetic field radiated by elementary dipoles
• Motion of a charged particle in an EM field
• Invariance of the magnetic moment linked to the motion of a charged particle in a slowly variable magnetic field
• Magnetic mirrors
• Ionized gases and interactions between their particles
• Radiative processes in a plasma
• Plasma characteristics and its motion
• Thermodynamic equilibrium in plasmas
• Debye length and plasma frequency
• Plasma sheaths
• Electrical conductivity and Hall parameter: the Ohm-Hall law
• MHD approximation and magnetic regimes
• Magnetic Reynolds number, magnetic interaction and Hartmann parameter
• The discharge in gases
• Magneto-Hydro-Dynamic (MHD) interaction
• Dielectric barrier discharges (DBD discharge) and Electro-Hydro-Dynamic (EHD) interaction

Readings/Bibliography

The complete series of slides of the course, are the course notes available at the teacher's website (http://www.die.ing.unibo.it/pers/borghi/carlo.htm). The recommended texts for consultation and details are:

• Julius Adams Stratton, “Electromagnetic Theory”, McGraw Hill, 1941
• J.D. Jackson, "Classical Electrodynamics", John Wiley and Sons, New York, 1975
• L. Spitzer, "Physics of Fully Ionized Gases", Interscieces, 1962
• R.J. Rosa, "Magnetohydrodynamic Energy Conversion", McGraw Hill, 1968
• M. Mitchner and C.H. Kruger, "Partially Ionized Gases", John Wiley and Sons, New York, 1973.
• J.R. Roth, "Industrial Plasma Engineering", Institute of Physics Publishers, Philadelphia, 1995-2000

Teaching methods

The course will be held by lectures given by the teacher who will use  a slide show.

Assessment methods

The exam is oral. Every Tuesday the exam be done by appointment with the teacher through an e-mail (ca.borghi@unibo.it).

Teaching tools

The slides projected during the lessons are the course notes. A pdf version of them are available on the teacher's website (http://www.die.ing.unibo.it/pers/borghi/carlo.htm).

Office hours

See the website of Carlo Angelo Borghi