Liquid compressibility effect on the acoustic generation of free radicals

Even through the liquid compressibility effect on acoustic cavitation has already been investigated by several authors, their results, however, are still limited to the radial dynamics and the thermodynamic behavior of the gas inside the bubble. In this computational study, the effect of liquid compressibility was investigated on both the bubble dynamics and the resulted chemical reactions inside the bubble at the collapse. Two cavitation models, based on Rayleigh-Plesset (RP) equation for incompressible medium and that of Keller-Miksis (KM) for compressible one, were adopted. A reaction scheme consisting on 25 reversible reactions was used for simulating the chemistry occurring inside the bubble at the strong collapse. The inclusion of liquid compressibility induced lower bubble temperature (T-max), pressure (p(max)) and chemical yield of the oxidants inside the bubble at the strong collapse. Furthermore, frequency and acoustic strongly affected the effect of liquid compressibility.