Cavitation dans les espaces très confinés : quelques exemples

Cavitation in very confined spaces: some examples

Groupe Phénomènes d'Interface, Ecole Nationale Supérieure de Techniques Avancées

Abstract

By a simplified definition, cavitation occurs when the local pressure is equal or smaller than the vapour pressure of the flowing liquid, regardless of the dimension of the domain are very large as compared to the zones where cavitation can exists. However, there is a certain number of situations in internal hydrodynamics where the liquid is confined between fixed or moving walls limiting spaces of very small dimensions, of the order of 10^-6 -10^-5 m. Typical examples of such situations are those encountered in lubrication, flow (or pressure) control by section restrictors, etc. The Groupe Phénomènes d'Interface of ENSTA has been involved for many years in research work on two areas of industrial application: one is related to the flow in control valves of car power steering systems and the other to the flow occuring in the vicinity of the contact between a rotatintg cylinder or sphere with a fixed flat or cured wall. The purpose of this communication is to present some experimental results on the cavitation phenomena in these two flow configurartions.