表面活性剂溶液粗粒化模型couette流动模拟

A Coarse-grain Molecular Dynamics Simulation for Surfactant Aqueous Solution in Couette Flow

本文主要利用粗粒化分子动力学方法对不同浓度下表面活性剂水溶液在couette流动过程中胶束的形成、速度分布与流变性规律进行了研究。结果表明,对于相同浓度的表面活性剂溶液,随着剪切速率的增大,胶束完全动态平衡时间越来越小;而随着表面活性剂分子浓度的增加,胶束动态平衡时间也越来越小,形成胶束越来越快。在剪切速率与溶液剪切黏度关系方面,保持表面活性剂分子浓度不变情况下,随着剪切速率的增大,剪切黏度逐渐减小,呈现剪切稀化特征。

In this paper, the formation of micelle, velocity distribution, and rheological behavior in surfactant aqueous solution under couette flow were studied using coarse-grained molecular dynamics simulations. Simulation results show that the dynamic equilibration time becomes shorter with the increase of shear rate on the condition of the same surfactant aqueous solution concentration. If the shear rate is a constant number, the formation of a micelle was more rapid when the surfactant molecular concentration increases in the aqueous solution. When the surfactant molecular concentration keeps constant, the shear viscosity becomes smaller with the increase of shear rate, and the shear-thinning characteristic can be obtained.