Hydromagnet: A Self-Generating Liquid Conductor Electromagnet

Abstract

A novel liquid electromagnet is investigated in which the exciting current is generated within the solenoid by forcing the liquid conductor radially inward through the space between two coaxial cylinders placed in an axial magnetic field. The tangential current thus generated within the flowing conductor adds to the initial applied field so that the device behaves like a self‐excited, short‐circuited homopolar generator. It is shown theoretically that for low values of the magnetic Reynolds number, the amplification of the magnetic field is a quadratic function of this number and that the total dissipation depends on the square of the amplification and on the cube of the hydrodynamic Reynolds number. The experimental findings are in reasonable agreement with the theory.