Multipole expansion for transient electric and magnetic fields in an internally excited spherical cavity containing dampers of finite thickness with distributed electrical properties
Abstract
The multipole expansion coefficients needed to calculate transient electromagnetic fields and cavity frequency response in an internally excited, damped cavity are derived for an arbitrary but centralized distribution of source currents and an arbitrary number of dampers which have finite width. A block matrix procedure is devised to solve the N damper boundary value problems, but specific solutions are presented for the cases of zero, one, and two dampers. Also, the TM wave multipole coefficients for an uncapped biconical antenna used as excitation source are obtained in closed form, with use of Schelkunoff's mode solution for the antenna currents. Finally, coupled integrodifferential equations for the current distribution in the end caps and the conical sections of a capped bicone source are presented. This entire theory will be encoded to permit analysis of AEDC experiments.
 Publication:

Final Report
 Pub Date:
 October 1981
 Bibcode:
 1981aro..reptR....C
 Keywords:

 Antennas;
 Conical Bodies;
 Electromagnetic Fields;
 Nuclear Explosions;
 Radiation Effects;
 Spherical Coordinates;
 Boundary Value Problems;
 Current Distribution;
 Differential Equations;
 Simulation;
 Communications and Radar