Theoretical Prediction Of Free Radical Production In Oxygen Bubbles Under Acoustic Cavitation

With the development of economy and the discharge of various kinds of sewage,the shortage of water resources has become one of the most important problems.In order to solving this problem,one should advocate to save water,increase the solution of waste water,realize the recycling of waste water,reduce the pollution of the environment.Now,the degradation mainly use chemical,physical,biological methods,but each of them has their own limitations.Ultrasound is a novel physical method which has some advantages compared with the tradition methods,such as mild condition,wide range of application and no secondary pollution.However,without practice in engineering,it is blind to infer theoretical basis on experiment results.Considering liquid compressibility,viscosity,surface tension,heat and mass transport,radiation damping,evaporation and condensation of water vapor,mass transfer of gas vapor and chemical reactions in the bubble,the dynamical behaviors of cavitation bubble clusters and a single bubble and the number of oxides inside the bubble are numerically investigated under acoustic field,regarding water as a work medium.The effects of acoustic frequency,acoustic pressure amplitude,driving waveform,liquid viscous,surface tension,the initial radius and the number of bubbles inside a bubble cluster on temperature and the strong oxides production inside collapse bubbles are analyzed.The results show that the changes of acoustic frequency,acoustic pressure amplitude,the initial radius and the number of bubbles inside a bubble cluster not only have an effect on temperature and the radical production inside the bubble,but also influence the degradation species of pollution,which provides a guidance for improving the degradation of water pollution.