Stability of a Perfectly Conducting Liquid Jet in the Presence of a Magnetic Field

Abstract

The stability of a cylindrical jet of a perfectly conducting, incompressible, and inviscid fluid in the presence of an axial magnetic field is studied for both axisymmetric and asymmetric disturbances. It is found that the jet becomes stable against disturbances of any wavelength when the magnetic field strengths are sufficiently high both inside and outside the jet, so that the Alfvén wave velocities at these places are greater than the undisturbed velocities of the fluid there. When the magnetic field strengths are not sufficiently high, the jet becomes unstable, and the critical wavenumber for those disturbances at which the instability first sets in is calculated in the axisymmetric case with the fluid outside the jet taken to be at rest.