The Euler number—Technological challenges of cavitation

Peter Monkewitz*, Flavio Noca and Etienne Robert, Laboratory of Fluid Mechanics, Swiss Federal Institute of Technology, Lausanne

* This Invited Lecture will be presented by Peter Monkewitz

The Euler number is essentially the ratio of the typical static pressure minus the vapor pressure and the typical dynamic pressure in a given flow. It therefore characterizes the propensity of the flow to cavitate, i.e. to form vapor bubbles. The technological importance of the phenomenon is shown on two examples—The abrasion of a solid by micron size particles (as for instance in a “wire saw”) and the dynamics of laser generated cavitation bubbles in a liquid jet.