基于CFD瞬态模拟的搅拌空化对微胶囊粒径调控机制研究
Study on regulation mechanism of microcapsule particle size by stirring cavitation based on CFD transient simulation
安金亮 1田子厚1
作者信息
- 1. 河北工程大学土木工程学院，河北邯郸 056000
- 折叠
摘要
为明确搅拌过程中空化现象对微胶囊粒径及其分布的影响机制，基于计算流体力学（computational fluid dynamics，CFD）瞬态模拟方法，对不同搅拌转速条件下反应器内的流场特性及空化行为进行了系统研究。通过建立烧杯搅拌模型，模拟分析了550~850 r/min范围内不同转速下的流体体积分数分布、流线结构、湍流动能及剪切应力场特征，并结合实验制备结果，探讨流场变化与微胶囊粒径演化之间的关联关系。结果表明：随着转速的升高，流场湍动程度和局部剪切应力显著增强，空化现象逐渐加剧，对微胶囊破碎与粒径分布产生明显影响；其中，在650 r/min条件下，反应器内流场分布相对均匀，剪切应力适中，空化强度得到有效控制，所制备微胶囊粒径分布最为集中。实验结果与CFD模拟结果一致。研究表明，合理控制搅拌转速可有效调控空化行为，从而实现对微胶囊粒径的精准调控。本研究可为微胶囊制备过程中搅拌参数的优化提供理论依据和数值参考。
Abstract
To clarify the influencing mechanism of cavitation phenomenon on the particle size and distribution of microcapsules during the stirring, the flow field characteristics and cavitation behaviors inside the reactor under different stirring speeds were systematically investigated based on the transient simulation method of Computational fluid dynamics (CFD).A beaker stirring model was established to simulate and analyze the characteristics of fluid volume fraction distribution, streamline structure, turbulent kinetic energy and shear stress field at rotational speeds ranging from 550 rpm to 850 rpm. Combined with the experimental preparation results, the correlation between flow field variations and the evolution of microcapsule particle sizes was explored. The results indicate that with the increase of rotational speed, the turbulence intensity of the flow field and local shear stress are significantly enhanced, and the cavitation phenomenon is gradually aggravated, which exerts a notable impact on the breakage and particle size distribution of microcapsules. Specifically, at a rotational speed of 650 rpm, the flow field distribution inside the reactor was relatively uniform, the shear stress was moderate, and the cavitation intensity was effectively controlled, leading to the most concentrated particle size distribution of the prepared microcapsules. The experimental results were consistent with the conclusions of CFD simulations. This study demonstrates that reasonable control of stirring speed can effectively regulate the cavitation behavior, thereby achieving precise control of microcapsule particle size,which provides a theoretical basis and numerical reference for the optimization of stirring parameters the microcapsule preparation.关键词
流场/搅拌过程/胶囊粒径/CFD模拟/空化现象Key words
flow field/agitation process/capsule particle size/CFD simulation/cavitation phenomenon引用本文复制引用
安金亮,田子厚.基于CFD瞬态模拟的搅拌空化对微胶囊粒径调控机制研究[EB/OL].(2026-05-14)[2026-05-15].http://www.paper.edu.cn/releasepaper/content/202605-53.学科分类
自然科学研究方法/力学
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