Theoretical model for predicting bubble formation from submerged orifices

Bubble diameter formed at submerged orifices is crucial and challenging to predict with a reliable universal model. A theoretical model covering a wide range of pore structures, operating conditions, and liquid properties for predicting bubble diameter based on bubble force equilibrium at the bubble detachment moment was proposed and verified with good prediction accuracy. The bubble-induced liquid velocity was incorporated to improve the prediction accuracy, and its underlying mechanism on bubble formation diameter was revealed. Additionally, the influencing mechanisms of orifice size, gas inlet velocity, and principal fluid properties on bubble formation diameter were elaborated systematically based on the new mathematical model, and the abnormal phenomenon of bubble formation under high temperatures and elevated pressures is clarified. Based on the proposed high-precision mechanistic model, the theoretical foundations for designing and scaling up industrial aerated reactors and scientific boundary conditions for numerical simulation are provided.