Influence of phase-change on the collapse and rebound stages of a single spark-generated cavitation bubble

Abstract Influences of phase-change are generally ignored by current numerical models that are used to study spark-generated cavitation bubble dynamics. However, this assumption was limited to predicting bubble behaviors only at the first expansion and collapse stages. In this study, we aimed to explore the phase-change effects on the cavitation bubble dynamics over multiple cycles. A combination of a two-phase homogeneous mixture model and interface-capturing method was adopted to simulate the bubble dynamics. The full compressibility of the water and vapor phases, heat transfer, condensation, and evaporation were involved in our numerical model. Phase-change processes due to pressure changes and temperature changes were evaluated to explore the major influence phenomenon on the bubble dynamics. By comparing with experimental data, a compatible bubble shape and radius evolution under a free-field condition was obtained, particularly at the rebound and collapse stages. Disturbance secondary cavitation regions in the water field induced by rarefaction waves were observed immediately after the second rebound stage. In addition, bubble dynamic behaviors were mainly affected by the condensation phenomenon. The condensation mass transfer rate increases, becomes extremely high at the final collapse stage, and decreases during the rebound stage. Moreover, the condensation phenomenon mainly occurs at the vapor–water bubble interfaces with a thin boundary layer. The evaporation phenomenon occurred purely inside bubbles with a uniform region. Finally, we discuss the effects of phase-change by temperature changes on the cavitation bubble dynamics. In general, these effects were sufficiently small during the first two-cycle bubble oscillations.