Multibubble Sonoluminescence from a Theoretical Perspective

Abstract

In the present review, complexity in multibubble sonoluminescence (MBSL) is discussed. At relatively low ultrasonic frequency, a cavitation bubble is filled mostly with water vapor at relatively high acoustic amplitude which results in OH-line emission by chemiluminescence as well as emissions from weakly ionized plasma formed inside a bubble at the end of the violent bubble collapse. At relatively high ultrasonic frequency or at relatively low acoustic amplitude at relatively low ultrasonic frequency, a cavitation bubble is mostly filled with noncondensable gases such as air or argon at the end of the bubble collapse, which results in relatively high bubble temperature and light emissions from plasma formed inside a bubble. Ionization potential lowering for atoms and molecules occurs due to the extremely high density inside a bubble at the end of the violent bubble collapse, which is one of the main reasons for the plasma formation inside a bubble in addition to the high bubble temperature due to quasi-adiabatic compression of a bubble, where “quasi” means that appreciable thermal conduction takes place between the heated interior of a bubble and the surrounding liquid. Due to bubble–bubble interaction, liquid droplets enter bubbles at the bubble collapse, which results in sodium-line emission.

Numerical simulations for sonochemistry

“…The important questions are as follows. What is the chemical activity of bubble clusters [93] , [94] , [95] ? What is the role of bubble-shape instability on chemical activity [93] , [96] ?…”

Acoustic characterization of cavitation intensity: A review

“…Cavitation usually refers to the generation of cavities and the subsequent dynamic behaviors when a liquid suffers from a sufficient pressure drop [1] . Due to high temperature and pressure [2] , [3] , [4] , [5] , micro jet [6] , [7] , [8] , shock wave [9] , [10] , [11] , light emission [12] , [13] , [14] and derived biochemical effects [15] , [16] , [17] in the process of cavitation, cavitation has been widely used in many fields, such as sonochemistry [18] , [19] , [20] , [21] , environmental engineering [22] , [23] , [24] , [25] , biomedical engineering [26] , [27] , [28] , material science [29] , [30] , [31] , [32] , food processing [33] , [34] , [35] , and so on. To estimate the cavitation effects and monitor the conditions of cavitation processes, cavitation detection and intensity characterization are desired.…”

A correlation between cavitation bubble temperature, sonoluminescence and interfacial chemistry – A minireview

“…The aim of this minireview is to provide a historical view of selected fundamental work on SL, SL quenching and the role of interfacial chemistry in understanding acoustic cavitation processes in the presence of surface-active solutes. It is worth noting that number of research and review articles are available that provide an advanced level discussion on the theoretical and experimental aspects of acoustic cavitation, sonoluminescence and sonochemistry [27] , [28] , [29] , [30] , [31] , [32] , [33] , [34] , [35] , [36] , [37] , [38] , [39] , [40] . Yasui has written excellent review articles on these topics [27] , [28] , [29] .…”

“…It is worth noting that number of research and review articles are available that provide an advanced level discussion on the theoretical and experimental aspects of acoustic cavitation, sonoluminescence and sonochemistry [27] , [28] , [29] , [30] , [31] , [32] , [33] , [34] , [35] , [36] , [37] , [38] , [39] , [40] . Yasui has written excellent review articles on these topics [27] , [28] , [29] . The numerical simulations for sonochemistry were discussed for single and multibubble sonochemistry.…”

“…A detailed discussion on acoustic cavitation and bubble dynamics [27] provides the readers to get an advanced understanding of this topic. Yasui also discussed [29] that the cavitation bubbles may be filled with a relatively higher amount of water vapour or noncondensable gases depending upon the acoustic frequency and power. The light emission from a plasma formed inside a bubble and the possibility of liquid droplet injection leading to atomic and molecular emissions contributing to SL is discussed.…”