Free-boundary vacuum arc plasma jet expansion in a curved magnetic field

A hydrodynamic model of free-boundary vacuum arc plasma jet flow through a curved magnetic field has been developed. The plasma flow was modeled by sourceless steady-state equations, and the free boundary of the plasma was determined as a part of the solution of the gas-dynamic equations. It was found that the maximum plasma density shifts with respect to the centerline. The shift is maximum at the 90° guide exit plane and for the case of low magnetic field. The maximum increase in longitudinal plasma velocity along the duct was shown to be a factor of three. The plasma distribution within the duct was analyzed experimentally using a deposition probe technique. The plasma jet expansion predicted by the model was compared with the experiment and a good qualitative agreement was found