Study on Time-Domain Thermal Characteristic of a Positive DC Arc on Ice Surface

An in- depth study of the thermal characteristics of the discharge channel is critical to revealing the discharge mechanism on the ice surface. This article uses the calibrated Schlieren method to study the discharge channel’s thermal characteristics (time-domain thermal radius and temperature characteristics) in the arc formation and propagation stages on the ice surface. The effects of the applied water conductivity, electrode-ice gap distance, and ice thickness on the thermal characteristics of the discharge channel are obtained. Results show that in the arc formation stage, the corona and brush discharge’s temperature is 440–550 K, and the thermal radius is 0.4–0.64 mm. The discharge channel’s growth rate of the temperature and thermal radius during the transition from spark to arc decreases with the increase of the ice thickness, the gap distance, and the applied water conductivity. The discharge channel’s thermal radius increases exponentially with the increase in temperature. In the arc development stage, the arc temperature increases with the increase of the arc’s thermal radius, and the arc’s thermal diameter increases logarithmically with the increase of leakage current.