Experimental study on the influence of the electric field on free surface waves

The influence of the electric field on surface waves in diesel oil is studied experimentally. The experimental device is mainly composed of a tank filled with diesel oil and two parallel metallic electrodes: one of them is immersed in the liquid and brought to a high potential, the other one is placed above the liquid. The surface waves are generated by a vibrator for which the frequency and amplitude of the vibrations can be controlled. The differences of potential applied can vary. Particle Image Velocimetry (PIV) is used to measure the velocity of the propagation waves on the diesel oil/air surface. The objective is to determine the influence of the electric field on the wavelengths at different amplitudes and frequencies as well as to calculate the surface tension. In this article we show that the apparent surface tension of the diesel oil decreases when the voltage is applied.