In order to investigate the variation of bubble diameter and the dynamics behavior of bubble inside the SFMBG(micro-bubble generator with swirl flow),the Euler-Euler inhomogeneous gas-liquid two-phase model was used to get flow parameters,and by coupling population balance model to compute the number density of the 14 bubbles with the diameter from 1 μm to 1 000 μm.Moreover,the bubble breakup and coalescence behavior inside the SFMBG was analyzed based on the Luo-breakup and Liao-coalescence combination model.As a result,the data of simulation is close to that of experiment,indicating that CFD-PBM(computational fluid dynamics population balance model)can be used to get knowledge of the variation of bubble diameter in SFMBG.Under the theoretical condition,the bubble breakup frequency is more sensitive to the liquid velocity change,while bubble coalescence frequency is more sensitive to the variation of local gas content.Besides,the gas phase is mainly distributed in the vicinity of the central axis of the SFMBG,and a large bubble area with tornado shape can be seen along the central axis;Most importantly,increasing liquid flow rate and decreasing outlet diameter can promote the reduction of the outlet bubble diameter.However,the effect of changing inlet gas flow on outlet bubble diameter is not sensitive,and this relationship is also influenced by the outlet diameter.
关键词
旋流式微泡发生器/二相流/计算流体力学/数值模拟/群体平衡模型
Key words
micro-bubble generator with swirl flow/two-phase flow/CFD/numerical simulation/PBM
维普
万方数据