The behaviors of an oscillating bubble near a water surface can be classified as forming a toroidal shape resulting from a re-entrant jet and an open bubble completely exposed to the atmosphere. In this study, we observe a phenomenon of partial ventilation. As the bubble expands, perturbations induced by the Rayleigh-Taylor instability grow rapidly on the water's surface and eventually penetrate the bubble wall, allowing ambient air to rapidly enter its interior. The bubble loses its transparency due to the considerable disturbance caused by high-speed airflow and various-sized droplets across its entire wall. Three distinct types of bubble behaviors with decreasing dimensionless standoff distance $\gamma$ are summarized in this study as follows: (i) nonventilation; (ii) partial ventilation; and (iii) complete ventilation, depending on the exposure of a bubble's interior to the surrounding air. The study investigates the partial ventilation phenomenon by combining laboratory experiments, numerical simulations, and analytical modeling. The analytical model comprises two components: a small-amplitude model that explains the growth of perturbations and a bubble-oscillation model that describes the bubble dynamics. Solving the model obtains the boundaries for the partial ventilation regime. These boundaries encompass upper and lower limits for both the dimensionless timing for starting ventilation $t_v^{\prime }$ and the dimensionless standoff distance $\gamma$. The analytical estimates agree well with the experimental observations and numerical results.

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• Bubble dynamics
• Cavitation
• Laser-induced cavitation