Simulation of the propagation in a capillary dielectric tube of an air discharge initiated by point-ring electrodes at atmospheric pressure

In this work, we have studied the dynamics and structure of an air discharge propagating in a capillary tube and initiated by a point-ring electrode geometry at atmospheric pressure. We have shown that the discharge velocity decreases as the discharge propagates in the dielectric tube. To increase the velocity of a given discharge after the cathode ring, we have shown that one can either decrease the tube radius or keep the same radius and increase the applied voltage or decrease the value of the tube permittivity. We have shown that the discharge becomes more homogeneous in the dielectric tube as the inner tube radius decreases and that the velocity of the discharge is higher if the discharge is more homogeneous. Finally, we have shown that the secondary emission coefficient has a negligible influence on the discharge velocity and structure. 1