高校化学工程学报2016，Vol.30Issue(6)：1264-1273,10.DOI:10.3969/j.issn.1003-9015.2016.06.005
载体液滴经微细管成形过程动力学特性的实验与模拟
Experimental and Simulation Studies on Dynamic Formation of Sodium Alginate Drops in Miniature Tubes
摘要
Abstract
Injection methods using micro or miniature tubes followed by crosslinking or pore-forming cryogenic steps are effective in the fabrication of microbeads or cryogel-beads with controllable bead size distribution. The droplet formation process is crucial to the final size of microbeads and it is important to investigate dynamic characteristics of the droplet formation process. In this work, high-speed imaging was employed to study dynamic behaviors of sodium alginate droplet formation using different miniature tubes with inner diameters of 1.1, 1.6, 1.9 and 2.2 mm, respectively. The effects of tube diameter on droplet formation, dripping speed, diameter distribution and micro-thread length were investigated. Geometric reconstruction based on piecewise linear interface construction (PLIC) of the volume of fluid (VOF) method was used to capture gas-liquid interface, and the droplet generation process was numerically simulated. The experimental results show that drip velocity, mean diameter and micro-thread length of the sodium alginate droplets increase with the increase of tube diameter. For 2%(w/w) sodium alginate solution under tube inner diameter of 2.2 mm at flow velocity of 30 mm×s-1, the maximum micro-thread length is 9.24 mm, the dripping speed is 6.09 mm×s-1 and the mean diameter of droplets is 5.8 mm. These values are 119.04%, 129.81%and 39.13%higher than those obtained with tube inner diameter of 1.1 mm, respectively. The simulation results show that compared with experimental results, the maximum relative errors of the micro-thread length, dripping velocity and mean diameter of the droplets are 8.7%, 2.1%and 8.6%, respectively, which indicates that the simulation method is effective for describing and simulating droplet formation processes of non-Newtonian fluids like sodium alginate solution with micro or miniature tubes.关键词
载体液滴/海藻酸钠微球/微细管/高速摄像/动力学/数值模拟Key words
droplets/sodium alginate microspheres/miniature tube/high-speed imaging/dynamics/numerical simulation分类
化学化工引用本文复制引用
杨玉军,张玮,郑三龙,徐林红,陈冰冰..载体液滴经微细管成形过程动力学特性的实验与模拟[J].高校化学工程学报,2016,30(6):1264-1273,10.基金项目
浙江省自然科学基金(LY14B060005)；国家自然科学基金(21106132，21576240)。 （LY14B060005）
