Potential scanning for the phenomenon of charge elimination through a charge-relaxing EHD surface wave onto a domain previously traversed by an onset EHD wave

The polarity-dependent corona-driven EHD onset wave domains were produced, over varying charging parameters, to provide background conditions for launching charge-relaxation solitary waves in oil films by means of point earthing. These latter waves were all found to come to an ultimate stop owing to back-corona quenching. The overall final residue charge domains were scanned for potential along a diameter. Observation was that, outside the solitary front, potential is largely unaffected but charge removal leads to its spatial profile having a minimum at the center. These results are consistent with the concept that charge is being removed during expansion through partial corona neutralization, a mechanism analogous to that in the theory recently advanced for passive charge elimination from an insulator surface.