Study on the atmospheric pressure homogeneous discharge in air assisted with a floating carbon fibre microelectrode

Abstract

Based on the consideration of increasing the number of initial electrons and providing an appropriate distribution of electric field strength for discharge space, a method of adopting the wire-cylindrical type electrode structure with a floating carbon fibre electrode to achieve atmospheric pressure homogeneous discharge (APHD) in air is proposed in this paper. Studies of the electrode characteristics show that this structure can make full use of the microdischarge process of the carbon fibre microelectrode and the good discharge effect of the helical electrode to provide plenty of initial electrons for the discharge space. Besides, the non-uniform electric field distribution with gradual change leads to the slow growth of electron avalanches in this structure. Thus, the initial discharge voltage can be reduced and the formation of filamentary discharge channels can be inhibited, which provides theoretical possibilities for the homogeneous discharge in atmospheric air. Experiments show that a three-dimensional uniform discharge phenomenon can be realized under a 6.0 kV applied voltage in a PFA tube of 6 mm inner diameter, displaying good uniformity and large scale.