Abstract: Homogenous discharges were produced in a 2-mm air gap at atmospheric pressure by using 325# fine wire mesh as electrodes covered with 0.1 mm PET films and 50Hz line power source paralleled with a discharge-stabilizing capacitor. For obtaining such a homogeneous discharge it is important to attach tightly the wire mesh together with the PET film on the surface of a Rogowski electrode. The experiments show that the commonly used method to distinguish a homogenous discharge from a non-homogeneous one by the waveforms of discharge current and transferred charge is not always reliable since the waveforms could tell only the discharge simultaneity rather than the discharge homogeneity. A fast image of discharge with an exposure time not longer than 100ns should be used instead to judge the discharge homogeneity. It is the first time in the experiments of atmospheric pressure discharge using wire mesh electrode covered by PET film such fast images were obtained, which indicates that the homogeneous discharge is a Townsend discharge rather than a glow discharge.

Keywords: 
• atmospheric pressure glow discharge /
• wire mesh electrode /
• electret /
• fast imaging