A Transient, Axisymmetric Formulation for Modeling of Composite Materials

The electrically small loop is of great practical importance in finding direction and probing magnetic fields. In [1], it was proposed for communication from above ground to observation points within coal mines. In this paper, the interactions of electromagnetic field, produced by a current-excited small loop, with lossy and lossless materials are investigated. The use of a small loop for the NDE of composite materials is also presented. To achieve these goals, solutions of interface problems become necessary. Since the exciting current is not restricted to be time-harmonic, we will solve the problems in the time domain. Also, to obtain economic requirements for computer resources, both storage and running time, a potential approach instead of vector field codes is developed

Solving time-dependent two-dimensional eddy current problems

Results of transient eddy current calculations are reported. For simplicity, a two-dimensional transverse magnetic field which is incident on an infinitely long conductor is considered. The conductor is assumed to be a good but not perfect conductor. The resulting problem is an interface initial boundary value problem with the boundary of the conductor being the interface. A finite difference method is used to march the solution explicitly in time. The method is shown. Treatment of appropriate radiation conditions is given special consideration. Results are validated with approximate analytic solutions. Two stringent test cases of high and low frequency incident waves are considered to validate the results

A Transient, Axisymmetric Formulation for Modeling of Composite Materials

The electrically small loop is of great practical importance in finding direction and probing magnetic fields. In [1], it was proposed for communication from above ground to observation points within coal mines. In this paper, the interactions of electromagnetic field, produced by a current-excited small loop, with lossy and lossless materials are investigated. The use of a small loop for the NDE of composite materials is also presented. To achieve these goals, solutions of interface problems become necessary. Since the exciting current is not restricted to be time-harmonic, we will solve the problems in the time domain. Also, to obtain economic requirements for computer resources, both storage and running time, a potential approach instead of vector field codes is developed.</p