Dielectric Fluid in Inhomogeneous Pulsed Electric Field

TL;DR

This paper investigates how inhomogeneous pulsed electric fields induce cavitation in dielectric fluids due to electrostrictive forces, highlighting the effects of voltage rise steepness and field shutdown on cavitation phenomena.

Contribution

It provides a detailed analysis of fluid dynamics under pulsed electric fields, emphasizing the conditions leading to cavitation and rupture in dielectric liquids.

Findings

Steep voltage rise fronts can cause negative pressures leading to cavitation.

Flatter voltage fronts do not induce cavitation.

Sudden shutdown of the electric field can trigger cavitation through reverse flow.

Abstract

We consider the dynamics of a compressible fluid under the influence of electrostrictive ponderomotive forces in strong inhomogeneous nonstationary electric fields. It is shown that if the fronts of the voltage rise at a sharp, needle-like electrode are rather steep (less than or about nanoseconds), and the region of negative pressure arises, which can reach values at which the fluid loses its continuity with the formation of cavitation ruptures. If the voltage on the electrode is not large enough or the front is flatter, the cavitation in the liquid does not occur. However, a sudden shutdown of the field results in a reverse flow of liquid from the electrode, which leads to appearance of negative pressure, and, possibly, cavitation.