Response of microscopic bubbles to sudden decrease of ambient pressure in viscous compressible liquid

A shock tube is used to investigate the bubble dynamics under sudden decrease of ambient pressure. Both the oscillating and monotonously growl bubbles were simultaneously observed. Theoretical approach is based, on the Rayleigh-Plesset and Herring's equations for incompressible and compressible liquids, respectively. Considering the linear approximation of these equations for the quasiequllibrium state, two critical Weber numbers are defined. They enable one to predict the following modes of the bubble expansion: (i) unbounded growth, (ii) asymptotic growth to limited volume and (iii) attenuated oscillations, depending on the pressure force, viscosity and compressibility of the liquid.