%0 Journal Article
%T Numerical Simulation and Investigation of System Parameters of Sonochemical Process
%A Sankar Chakma
%A Vijayanand S. Moholkar
%J Chinese Journal of Engineering
%D 2013
%R 10.1155/2013/362682
%X This paper presents the effects of various parameters that significantly affect the cavitation. In this study, three types of liquid mediums with different physicochemical properties were considered as the cavitation medium. The effects of various operating parameters such as temperature, pressure, initial bubble radius, dissolved gas content and so forth, were investigated in detail. The simulation results of cavitation bubble dynamics model showed a very interesting link among these parameters for production of oxidizing species. The formation of £¿OH radical and H2O2 is considered as the results of main effects of sonochemical process. Simulation results of radial motion of cavitation bubble dynamics revealed that bubble with small initial radius gives higher sonochemical effects. This is due to the bubble with small radius can undergo many acoustic cycles before reaching its critical radius when it collapses and produces higher temperature and pressure inside the bubble. On the other hand, due to the low surface tension and high vapor pressure, organic solvents are not suitable for sonochemical reactions. 1. Introduction The sonochemistry concept is a well-established technique, and now it is considered as one of the most popular advanced oxidation processes. In the last few decades, sonochemical process became one of the most popular techniques for synthesis of catalysts as well as different types of materials [4¨C7], degradation of pollutants [8¨C12], synthesis of biodiesel [13, 14], and so forth. Numerous literatures on sonochemistry have already been published [15¨C18] which reported the various beneficial effects of sonochemistry. The principal phenomenon behind all of these effects is the cavitation. Cavitation is nothing but nucleation, growth, and implosive collapse of a bubble. Cavitation occurs through the formation of bubbles or cavities present in liquid medium. Each cavitating bubble contains gas or vapor or a mixture of gas-vapor. When bubble contains only gas, the expansion of bubble is mainly by diffusion, pressure reduction, or by rise in temperature. However, there are several parameters which are directly involved in transient cavitation. Transient cavitation is nothing but the growth of bubbles extensively over time scales of the order of the acoustic cycle and then undergoes an implosive/energetic collapse resulting in either fragmentation, decaying oscillation, or a repeat performance [19]. Cavitation can also be the result of the enlargement of cavities that are already present in bulk liquid. Sometimes cavitation bubbles are
%U http://www.hindawi.com/journals/cje/2013/362682/