Bubble collapse induced cavitation erosion: Plastic strain and energy dissipation investigations

Shrey Joshi (1) , Jean-Pierre Franc (2) , Giovanni Ghigliotti (2) , Marc C. Fivel (1)

1 SIMaP - Science et Ingénierie des Matériaux et Procédés
2 LEGI - Laboratoire des Écoulements Géophysiques et Industriels [Grenoble]

A meshless Smoothed Particle Hydrodynamics solver is used to simulate the collapse of a cavitation bubble near a solid material taking into account the complex fluid-structure interaction. A parametric study has been performed to study the effect of stand-off ratio, bubble size, driving pressure and strain rate on the material response. We focus on plastic strain magnitudes and plastic strain energy dissipation to compare different cases and their ability to cause material erosion. Findings indicate that, in the case of repeated collapses, cavities attached to the solid have an ability to initiate damage quicker but exhibit lower erosion rate compared to the cavities detached from the solid. The incubation time does not depend on the size of the bubbles, unlike the erosion rate which is strongly affected by the bubble size. It is also found that the amount of cumulated plasticity is overestimated by more than 150% when the strain-rate sensitivity is not taken into account in the material modelling which suggests that using an appropriate plasticity model that includes strain-rate sensitivity is mandatory while studying the phenomenon of cavitation erosion.

Mots clés: Cavitation erosion; Fluid-structure Interaction; plastic strain energy dissipation; strain rate effects; stand-off distance

Domaines: Mécanique des fluides [physics.class-ph]; Mécanique des matériaux [physics.class-ph]

Shrey Joshi, Jean-Pierre Franc, Giovanni Ghigliotti, Marc C. Fivel. Bubble collapse induced cavitation erosion: Plastic strain and energy dissipation investigations. Journal of the Mechanics and Physics of Solids, 2020, 134, pp.103749. ⟨10.1016/j.jmps.2019.103749⟩. ⟨hal-02318089⟩