Cavitation over solid surfaces: microbubble collapse, shock waves, and elastic response

• Published in: Meccanica (Milan) Vol. 58; no. 6; pp. 1109 - 1119
• Main Authors: Abbondanza, Dario, Gallo, Mirko, Casciola, Carlo Massimo
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.06.2023; Springer Nature B.V
• Subjects: Automotive Engineering; Cavitation; Civil Engineering; Classical Mechanics; Collapse; Complex systems; Compression waves; Engineering; Longitudinal waves; Mechanical Engineering; Overpressure; Plastic deformation; Rayleigh waves; Shock waves; Solid surfaces; Topology; Wave propagation; Bubble dynamics; Elastic waves; Phase field method; Cavitation
• DOI: 10.1007/s11012-022-01606-5
• ISSN: 0025-6455

We discuss the interaction of the strongly nonlinear fluid motion induced by the collapse of a vapor microbubble over a planar surface and the elastic dynamics of the underlying solid. The fluid is described using an extension of the Navier-Stokes equations endowed with distributed capillary stresses in the context of a diffuse interface approach. The collapse of the bubble is triggered by overpressure in the liquid and leads to an intense jet that pierces the bubble, changing the bubble topology from spheroidal to toroidal, and impinges the solid wall inducing an intense and strongly localized load. Moreover, at bubble collapse, a compression wave is launched into the liquid surrounding the bubble. By propagating along the solid surface, the compression wave combined with the liquid jet excites the dynamics of the elastic solid, producing a complex system of waves, including, longitudinal, transversal, and Rayleigh waves, propagating in the solid. It is conjectured that the intense deformation of the solid induced by the strongly localized liquid jet may lead to the plastic deformation of the solid producing the surface pitting observed in many applications subject to cavitation-induced material damage.