液滴传质过程中Marangoni对流的引发

(厦门大学化学化工学院,福建 厦门 361005)

Marangoni效应; 计算流体力学; 对流扩散; 传质; 数值模拟

Initiation of Marangoni convection in mass transfer of liquid drop
QI Jiangyu,YANG Jie,SHA Yong*

(College of Chemistry and Chemical Engineering,Xiamen University,Xiamen 361005,China)

Marangoni effect; computational fluid dynamics; convection diffusion; mass transfer; numerical simulation

DOI: 10.6043/j.issn.0438-0479.201806001

备注

对在丙酮-甲苯-水体系中由于传质而引发的Marangoni效应进行数值模拟,比较了二维和三维模型模拟计算结果中丙酮相对质量浓度和界面平均流动速度等参数在传质过程中的差异.结果表明两种模型计算结果差异较大,三维模型中Marangoni对流引发得更加充分,更贴近于实际情况.随后在三维模型中,分别考察了Gibbs吸附层与丙酮初始质量浓度对传质的影响,与文献中实验结果对比发现液-液界面中Gibbs吸附层的影响可以忽略,而丙酮初始质量浓度越高,Marangoni对流的引发时间越早,强度越大.

Marangoni effect induced by mass transfer process in the acetone-toluene-water droplet was numerically simulated.Relative mass concentration of acetone and average interface flow velocity of 2D and 3D models were compared.The results showed that the calculation of the two models was quite different,and the convection simulated by the 3D model was closer to the actual situation.Marangoni effect is a phenomenon that occurs in three dimensions,so it is not reasonable to simplify this 3D phenomenon to a 2D phenomenon.For the 3D droplet model,the effects of Gibbs adsorption layer and initial acetone concentration on mass transfer were tested.Compared with the experimental studies from literature,the results showed that the influence of Gibbs adsorption layer appearing in the liquid-liquid interface could be ignored.For liquid droplets with different initial acetone mass concentration,the higher initial mass concentration corresponded to the shorter critical time and the stronger intensity of the Marangoni convection.