Efficiency of magnetic plasma filters

The curvilinear filter version is currently most generally employed in both laboratory and industrial practice. However, its complexity, low efficiency and far from ideal filtering ability preclude it from being used more widely. Research and development performed by the Kharkov group of physicists to improve the situation are described in this paper. Recent experiments on defining the special features of curvilinear plasma filters and their dependence on electromagnetic and geometrical parameters are described. The paper demonstrates the possibility and advisability of improving and optimizing the filtering, and predicts, through computer simulation, the macroparticle motion along the plasma duct, taking into consideration multiple rebounds of particles from the walls. The proposed method of estimating the efficiency of macroparticle flow suppression combined with the computation of magnetic field distribution in the transport channel of the filter makes it possible to optimize the system in two criteria: (i) maximum removal of macro-particles from plasma; and (ii) minimum loss of the ion component of the plasma. Examples of present-day applications are given, and the potential use of filtering. Some alternative versions of magnetic plasma filters are described. The transmission coefficient for an optimized knee-shaped filter reaches 68%, this being the highest value compared with other similar designs. A new source forming a radial flow of filtered plasma is characterized by the ∼90% transmission coefficient and the ∼8.5% system efficiency. This is three to seven times higher than the corresponding parameters for other known systems.