Sound Generation by Magnetohydrodynamic and Joule Heating Mechanisms in a Fluid

date October 17, 1986
comments no comments.

Friday, 17 October 1986 12:00 p.m.

Stephen Schreppler
Applied Research Laboratories
The University of Texas at Austin

When an electrical current passes through a resistive fluid in the presence of a magnetic field, two mechanisms for sound generation are present. The interaction of the electrical current with the magnetic field results in the Lorentz force which acts on the fluid. If the current is time dependent, the Lorentz force (the magnetohydrodynamic sound mechanism) creates an acoustic disturbance. Joule heating is also associated with the passage of electrical current through the fluid. The heating, which results from the dissipation of electrical power, causes a perturbation of the fluid density and is thus another mechanism for sound generation. The unique properties of these mechanisms and results of experiments performed at the Applied Research Laboratories will be discussed.