Excitation of low-frequency oscillations on water surface in electrostatic field

The behavior of a dielectric liquid in the interelectrode gap with an electric charge induced on one of the two electrodes has been experimentally studied. The effect of an electrostatic field on the immobile water surface has been determined for an applied voltage within 1000 V ≤ U ≤ 12 000 V. The formation of cone-shaped protrusions on the liquid surface is limited by plasma discharge, which induces cyclic oscillations in the liquid at a constant frequency f. A further increase in the applied potential leads to stepwise changes in the oscillation frequency. Initial variation of the potential within 500–900 V is not accompanied by any significant change in f, but the subsequent increase in U within a narrow interval (20–40 V) leads to a resonant change in the oscillation frequency.