Comparison of Korteweg-Helmholtz Electromagnetic Force Density and Magnetic Charge Force Density in Magnetic Systems

자기시스템의 Korteweg-Helmholtz 전자력 밀도와 자하 전자력 밀도의 비교

  • 이세희 (성균관대 전기전자 및 컴퓨터공학부) ;
  • 최명준 (성균관대 전기전자 및 컴퓨터공학부) ;
  • 박일한 (성균관대 전기전자 및 컴퓨터공학부)
  • Published : 2000.04.01


In magnetic systems, distribution of electromagnetic force density causes mechanical deformation, which results in noise and vibration. In this paper, Korteweg-Helmholtzs energy method and equivalent magnetic charge method are employed for comparison of their resulting distributions of force density. The force density from the Korteweg-Helmholtzs method is expresses with two Maxwell stresses on the inside and the outside fo magnetic material respectively. The other is calculated using the magnetic Coulombs law. In the numerical model of an electromagnet, their numerical results are compared. The distributions by the two methods are almost the same. And their total forces are also shown to be the same to the one calculated from the conventional Maxwell stress tensor. But the magnetic charge method is easier and more efficient in numerical calculation.


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