Effect of Corona Discharge on Liquid Dielectrics

1. A test cell suitable for use in bombardment studies on oils was developed. 2. Pure liquid paraffin, various cable oils, and ten hydrocarbons of known tupe molecular structure were studied, and it was found that a number of their characteristicsare changed by corona discharge. 3. The power factor of all samples increased with bombardment. 4. The one-minute d-c conductivity of bombarded samples was in most instances considerably lower than the a-c conductivity calculated from power-factor values. 5. Application of d-c potential to bombarded decalin for extended periods showed that the power factor and conductivity of the samples were thereby decreased considerably, the improvement being maintained only during and shortly after application of the potential. 6. The material responsible for the changes in power factor and conductivity, and produced during the bombardment, constitutes an extremely small portion of the bombarded oil. It consists of material which remains as residue during distillation of the bombarded oils at the temperatures and pressures used in these studies. 7. Currents resulting from application of identical a-c bombardment voltages to the cell were widley different for the various oils. 8. The gas evolution of the various oils under pombardment was widley different, generally more gas being obtained from the saturated than from the unsaturated compounds. 9. In practically all cases an increase in viscosity resulted from the bombardment of the oils.