Cavitation in liquid dielectric under nanosecond high-voltage impulse

We consider the appearance of a cavitation near a needle-shaped electrode under nanosecond high-voltage impulse. It was shown that the gas–liquid boundary moves in an opposite direction to the needle-shaped electrode under the influence of electric field on this boundary. It leads to an increase of the cavity volume. The comparison with experiment shows that the dependence of dielectric permeability on the electric field strength does not dramatically change the result of the numerical simulation whereas accounting for the liquid compressibility and the choice of the high-voltage electrode size are important. It was shown that the existence of the caviation bubbles do not always lead to electrical breakdown in dielectric liquid through the gas phase. (paper)