Sonoluminescence and multi‐bubble cavitation phenomena for selected research and industrial applications

Single bubble sonoluminescence (SBSL), multi‐bubble sonoluminescence (MBSL), multi‐bubble sonochemiluminescence (MBSCL) and other high power ultrasound cavitation and noncavitating ultrasound process stream interaction phenomena are known to produce a wide range of both physical and chemical effects that depend upon the system and operating conditions employed. Three interacting regimes are under investigation (a) high power and high frequency (including noncavitating systems), (b) single bubble resonance/sonoluminescence and (c) multi‐bubble high power sonochemical processing. In all cases these involve various reactors, including possible schemes for continuous material feeding and processing for selected chemical, nonaqueous fluids and biological research and industrial applications. High power sonochemical and noncavitating ultrasound processing applications and a review of literature pertaining to the potential of high power processing, including fusion are discussed. Work includes the investigation of acoustic fields in reactors, characterization of sonoluminescence spectra, the investigation of system parameters to control maximum bubble temperature and pressure, and acoustic energy partition into light and acoustic emission/shock waves. Effects of various chemical systems on multi‐bubble luminescence are being investigated and will be reported. Work to date has emphasized the evaluation of both single and multi‐bubble sonoluminescence, spectral measurements, acoustic emission measurements and the observation of a continuous bubble feed phenomenon.