Abstract:

Micro-bubble technology has many advantages and is involved in an increasing number of fields, while the Venturi structure can enhance turbulence and promote the generation of highly dispersed tiny bubbles and micro-bubbles. The behavior of bubbles in the Venturi bubble generator is mainly simulated by using the fluid simulation software FLUENT to understand the motion behavior of the bubbles in the Venturi tube, and the mechanism of bubble fragmentation is analyzed based on the simulation results. It is shown that the bubble fragmentation mainly occurs in the diffusion section, and the changes of velocity gradient, vortex collision and pressure are considered to be the key of bubble deformation and fragmentation; when the forces acting inside and outside the bubble are out of balance, the bubble will fragment into tiny bubbles flowing to the downstream region. This research can serve as a guide for further studies on mass transfer and has reference significance for industrial applications.

Key words:

摘要：

微气泡技术涉及到越来越多的领域，具有诸多优点，而文丘里结构能够增强湍流，促进高度分散的微小气泡和微气泡的产生。借助流体模拟软件FLUENT对文丘里气泡发生器中气泡行为进行模拟，了解了气泡在文丘里管中的运动行为，并根据模拟结果对气泡碎化机理进行了分析。结果表明，气泡的碎裂主要发生在扩散段，而速度梯度、涡流碰撞和压力的变化被认为是影响气泡变形和碎裂的关键因素，当气泡内、外部受力失衡时，气泡便会碎裂成微小气泡流向下游区域。该研究可为进一步研究传质起到指导作用，对工业应用有着借鉴意义。

关键词: 文丘里, 气泡发生器, 气泡碎化机理, FLUENT, 微小气泡, 边界条件, 气泡行为, 流场