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Longitudinal electrodynamic forces - and their possible technological applications

Master of Science Thesis by Lars Johansson,

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This thesis deals with the relatively unknown phenomena of longitudinal forces in conductors. A survey of relevant experiments is given. Ampere electrodynamics, which has been proposed to account for the phenomena, is compared with a Maxwell stress approach, and these are found to be equivalent. The relationship between different `action at a distance' theories is discussed. The role of relativistic electric fields, and electric fields from surface charges, is considered.

Several interesting applications such as metal punching, liquid metal pumping, water-arc jet propulsion, high current limiting and electrodynamic plasma fusion are covered, together with a novel application: the electrodynamic explosion motor.

Lund, September 19:th, 1996

(Thesis Adviser: Professor Gerhard Kristensson )

Department of Electromagnetic Theory
Lund Institute of Technology
P.O. Box 118
S-221 00 Lund, SWEDEN

Lars Johansson, Ms. Sc. Electrical engineering.
Lund, August 4:th, 1997