Study on transform mechanism between bubbling regimes and sizes at a submerged orifice in high temperature aerosol suspension

Abstract

Bubbling at a submerged orifice in pool is one of effective ways to filter radioactive gas in containment. Gas containing radioactive aerosol will rise in bubble column in the form of bubbles to be filtered. Complex environment in pool with high temperature and aerosol will affect the bubbling regimes and sizes, which involve the filtration efficiency by accompanying changes in surface area and floating velocity of bubbles. This paper observes and analyzes the transition between bubbling regimes and sizes at a submerged single-hole orifice in the high-temperature liquid pool containing barium sulfate or titanium dioxide particles through a visual experiment. The influence mechanism of environmental factors such as aerosol particles, temperature of liquid and gas feeding pressure are explored in the experiment. It is concluded that there will be a change in gas momentum force caused by changes in flow rate or pressure and a phenomenon that “cavity” ruptures in high-temperature aerosol suspension, both of which will cause the curvature change at the top of bubble and bubbling regimes change accordingly.