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 , 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.
KeywordsMagnetic Field Intensity Small Loop Great Practical Importance Artificial Boundary Radiation Boundary Condition
Unable to display preview. Download preview PDF.
- 1.J. R. Wait and K. P. Spies, “Subsurface electromagnetic fields of a circular loop of current located above ground,” IEEE Trans. Antennas Propagat., vol. AP-20, pp. 520–522, July 1972.Google Scholar
- 2.C. C. Lin and K. K. Mei, “Time Domain Absorbing Boundary Condition in Lossy Media,” presented at Int. IEEE/Antennas Propagat. Soc. Symp., Boston, MA, June 1984.Google Scholar
- 3.R. F. Harrington, Time-Harmonic Electromagnetic Fields, McGraw-Hill Book Company, 1961.Google Scholar
- 4.M. E. Lee, S. I. Hariharan, and N. Ida, “Solving time-dependent two-dimensional eddy current problems,” NASA Technical Memorandum, 100875 ICOMP-88–10, Lewis Research Center, Cleveland, OH, June 1988.Google Scholar
- 5.M. E. Lee, “Potential finite-difference time-domain methods for electromagnetic interface problems”, Ph. D. dissertation, Dept. of Elec. Eng., U. of Akron, Akron, OH, May 1989.Google Scholar