Numerical study of plasma beam propagation in a toroidal duct

A numerical solution of a self consistent two fluid hydrodynamic model for vacuum arc plasma beam propagation through a toroidal magnetic filter is obtained. In a toroidal magnetic field 5-20 mT the electrons are magnetized but ions are unmagnetized. In order to describe correctly the boundary conditions, duct curvature and centrifugal force a toroidal coordinate system was used. Electric field, current distribution, particle density and mass flows were calculated. The numerical results agree well with the principle experimental data: a) the duct efficiency does not exceed (8-10)% and it depends weakly on the magnetic field strength, b) at the torus exit maximum of plasma density distribution is displaced from the cross-section center in direction of vector product Bx g, were g is the ion centrifugal acceleration and B is the toroidal magnetic field