Experimental Studies of Ice Surface Discharge Inception and Development

Ultra-high-speed photographic techniques were used to observe and analyze the extremely rapid processes of corona streamer discharge inception and development on an ice surface during the first nanoseconds of occurrence. The studies were performed on a simplified physical model under a positive lightning impulse voltage. The physical model consists of two metallic hemispherical capped rods of 12 mm diameter half submerged in ice. The distance between the electrodes was 11 mm. A number of discharge parameters, such as inception field, critical volume, and propagation velocity, were investigated, discussed, and compared with the parameters obtained in an equivalent air gap.