0380977 - FZÚ 2013 RIV NL eng J - Journal Article
Vokoun, David - Beleggia, M. - Heller, Luděk
Magnetic guns with cylindrical permanent magnets.
Journal of Magnetism and Magnetic Materials. Roč. 324, č. 9 (2012), s. 1715-1719. ISSN 0304-8853. E-ISSN 1873-4766
R&D Projects: GA ČR(CZ) GAP107/11/0391; GA AV ČR IAA100100920
Institutional research plan: CEZ:AV0Z10100520
Keywords : permanent magnet * cylindrical magnet * Earnshaw's theorem * magnetic gun * magnetostatic interaction
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 1.826, year: 2012 ; AIS: 0.49, rok: 2012
Result website:
http://www.sciencedirect.com/science/article/pii/S0304885311008997DOI: https://doi.org/10.1016/j.jmmm.2011.12.026

The motion of a cylindrical permanent magnet (projectile) inside a tubular permanent magnet, with both magnets magnetized axially, illustrates nicely the physical principles behind the operation of magnetic guns. The force acting upon the projectile is expressed semi-analytically as derivative of the magnetostatic interaction energy. For comparison, the forces involved are also calculated numerically using finite elements methods. Based on the conservation of the magnetostatic and kinetic energies, the exit and asymptotic velocities are determined. The derived formulas can be used to optimize the generated forces and motion of the inner cylindrical magnet.
Permanent Link: http://hdl.handle.net/11104/0211557