Hydrodynamic relations for the oscillation of an underwater gas bubble are examined for their applicability to a number of available data sets for underwater implosions of glass globes (primarily lightbulbs). The measurements for peak frequency and peak pressure as a function of implosion depth suggest a damped resonance about the pressure equilibrium radius of the released bubble. Implications of power law dependencies among peak frequency, peak pressure level and implosion depth are discussed. Our results suggest that additional data are required to clarify the relation between implosion depth and peak frequency. Also, an empirical acoustic energy conversion efficiency is introduced to describe the strong damping observed in pressure time series.
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