气泡直径对旋流静态微泡浮选柱内流体动力学行为的影响

Effects of bubble diameter on the fluid dynamics in a cyclonic-static micro-bubble flotation column

本文针对新型旋流静态微泡浮选柱,利用ANSYS Fluent商业软件,基于欧拉-欧拉双流体模型,系统地模拟了汽泡直径对该浮选柱不同流段内的流体动力学行为的影响规律。气液间相间作用力采用Tomiyama曳力模型并忽略升力、壁面润滑力、湍流耗散力、虚拟质量力和浮力。湍流采用Realizable k-ε双方程模型。研究发现,气泡直径对气含率、湍动能及其耗散率、速度大小以及气泡竖直方向的速度分量均产生显著影响。随着气泡直径的减小,气含量和气液界面面积均增大,湍动能及其耗散率先增大后减小,气泡在柱内的停留时间增加。研究结果对该浮选柱的设计、优化具有指导意义。

A method based on Time Slice Model （TSM） is proposed for batch processes heat exchanger network synthesis by taking place. The effect of bubble diameter on the fluid dynamics of each section in a cyclonic-static micro-bubble flotation column was systematically simulated based on the Eulerian-Eulerian two-fluid model using ANSYS Fluent software. The Tomiyama model was used to express the drag force between phases. Lift force, wall lubrication force, turbulent dispersion force, virtual mass force and buoyancy force were ignored. The realizable k-ε model was used to express the turbulence in column. The results showed that, the bubble diameter markedly affected the gas holdup, turbulent kinetic energy, turbulent dissipation rate, velocity magnitude and velocity component in the erect direction for bubbles. With the decrease of bubble diameter, gas content and interfacial area between water and bubble increased, turbulent kinetic energy and its dissipation rate firstly increased and then decreased, the residence time also increased. This study had guiding significance during design and optimization.