Experimental study on the release of droplets via bubble bursting under different liquid phase conditions

Abstract When a gas passes through the surface of a liquid pool, bubbles are formed at the liquid surface.Thus, the liquid can be directly released into the atmosphere via bubble bursting above the pool surface.This phenomenon is prevalent in several fields, such as chemical industries marine aerosol environments, and nuclear engineering.If a liquid pool contains aerosols, the aforementioned phenomenon will directly become a means of releasing the through fall droplets.This is an important mechanism for releasing liquids and aerosols from pools.Therefore, it is important to study the phenomenon of bubble bursting and to derive the distribution of droplets to evaluate the mechanism of release.With this objective, an experimental visualization platform was designed; the process of bubble bursting was photographed using a high-speed camera,and the images were processed to obtain the distributions of the droplets released.The results shows that hundreds of droplets are formed via bubble bursting at the surface of the liquid, and the distribution of the droplets is different under different conditions of the liquid.In distilled water, the number of droplets formed via bubble bursting is less than in regular water, while the sizes of the droplets increase with an increase in temperature.Furthermore, in a suspension of TiO2at a temperature of about 16 °C, the mass concentration is not a key factor inthe release of the droplets.However, at high temperatures of about 50 °C and 77 °C,with an increasing mass concentration ofTiO2, the number of droplets formed via bubble bursting increases, while the dropletsizes decrease.This indicates that with an increase in the concentration of aerosols, more droplets and aerosols will be released via bubble bursting.