Accession Number : AD0288927

Title :   A SIMPLIFIED THEORY OF MAGNETOHYDRODYNAMIC ISOTROPIC TURBULENCE

Corporate Author : SPACE SYSTEMS DIV LOS ANGELES AIR FORCE STATION CALIF

Personal Author(s) : BETCHOV,R.

Report Date : 11 OCT 1962

Pagination or Media Count : 1

Abstract : The simplest case of turbulent motion in a conductive fluid is studied. The turbulence is assumed incompressible, isotropic, homogeneous, charge invariant and free of fourth-order cumulants. The emphasis is placed on certain integrals of the correlation functions such as kinetic and magnetic energy, vorticity, and current. A system of nonlinear ordinary differential equations is derived which governs these integral quantities. Several cases are solved numerically, illustrating the decay of ordinary turbulence, the buildup of magnetic energy by a linear or a nonlinear process, the buildup of kinetic energy, as well as the destruction of vorticity by Lorentz forces. In order to handle certain dissipative effects, a special hypothesis is introduced which seems to promote mathematical simplicity. In particular, it leads to a simple decay law very similar to the decay law of ordinary turbulence. (Author)

Descriptors :   *MAGNETOHYDRODYNAMICS, *TURBULENCE, CONVECTION, DEGRADATION, DIFFERENTIAL EQUATIONS, ENERGY, KINETIC THEORY, MAGNETIC PROPERTIES, MOTION, VORTICES

Distribution Statement : APPROVED FOR PUBLIC RELEASE