Interface stability of oil-water system under electric stress

The interface characteristics of oil-water system, under electric stress, are characterized through partial discharge (PD) measurements. Wavelet transform analysis is performed on the PD signals to yield unambiguous information of the events under electric stress. The intensity of PD as a function of electric stress is studied till the breakdown. A steady increase of PD magnitude as a function of electric stress is observed in the air-water system. Interestingly, the oil-water system displays three transition regions in the PD intensity vs electric stress plots. The dielectric properties of the oil-water system are affected by the electric stress significantly. The observed results are discussed in relation to the interface charges.