Thermal Characterization and Optimization of a Plasma Downstream Reactor for Particle Surface Modification

Abstract

Abstract A plasma downstream reactor for the continuous treatment of dry, cohesive, and temperature sensitive powders is investigated by means of fiber optic temperature measurements. A method to determine the different heat flux terms (plasma heating, radiation, and convection) is introduced and applied to calculate the inner wall and neutral gas temperature at several positions within the reactor. By this means undesirable discharge regions downstream the plasma zone are found. Consequently, the thermal characterization of the reactor allows optimization of the reactor design to confine the plasma to the downer tube and to avoid undesirable temperature hot spots.