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The Electromagnetic Phenomena as Incitants
Published in William J. Rea, Kalpana D. Patel, Air Pollution and the Electromagnetic Phenomena as Incitants, 2018
William J. Rea, Kalpana D. Patel
The more frequently used magnetic vector potential, A, is defined such that the curl of A is the magnetic B field. Together with the electric potential, the magnetic vector potential can be used to specify the electric field, E, as well. Therefore, many equations of electromagnetism can be written either in terms of E and B or in terms of the magnetic vector potential and electric potential. In more advanced theories such as quantum mechanics, most equations use the potentials and not the E and B fields.
Ultra-Wideband Antenna Technology
Published in James D. Taylor, Introduction to Ultra-Wideband Radar Systems, 2020
P. R. Foster, J. Doss Halsey, Malek G. M. Hussain
Because the divergence of a curl equals zero, B can be written as the curl of some other vector A which is called the magnetic vector potential. () B=∇×A
Statics and Quasistatics EIectromagnetics Brief Presentation
Published in João Pedro A. Bastos, Nelson Sadowski, Magnetic Materials and 3D Finite Element Modeling, 2017
João Pedro A. Bastos, Nelson Sadowski
The magnetic vector potential A is one of the most used potentials for magnetic problems. It is associated to the magnetic induction B by B=rotA $$ B = rotA $$
A Divergence-Free High-Order Spectral Difference Method with Constrained Transport for Ideal Compressible Magnetohydrodynamics
Published in International Journal of Computational Fluid Dynamics, 2021
In this paper, an unstaggered constrained transport (CT) framework proposed by Christlieb, Rossmanith, and Tang (2014) is used to satisfy the divergence-free condition in the discrete sense. Here a brief review of this framework is given. First, the divergence-free magnetic field is written as the curl of the magnetic vector potential Plugging Equation (36) into Equation (33), we obtain Using the Weyl gauge proposed in Helzel, Rossmanith, and Taetz (2011), the governing equation of the magnetic vector potential becomes For two-dimensional problems, it reduces to It is a hyperbolic partial differential equation. Therefore the spectral difference method can be a suitable method to solve it. The at element interfaces is calculated as its upwind value.
Comprehensive study on radial coil influence in designing segmented remote field eddy current probe for defect detection in ferromagnetic tubes
Published in Nondestructive Testing and Evaluation, 2022
T. Vijayachandrika, S. Thirunavukkarasu, B. Purna Chandra Rao
A 2-D axis-symmetric finite element model has been developed to understand axial and radial field components' influence on defect detection. COMSOL multiphysics software was used for the study, as shown in Figure 1. A frequency-domain model analysis has been carried out. The model consists of the tube, excitation coil and air domain. Material property and geometrical parameters of the tube are considered as listed in Table 1. The axial symmetry boundary along the symmetry line is set to Dirichlet boundary condition. The formulation is based on the magnetic vector potential. The governing equation is given by (1).