论文标题
类似蠕虫的胶束溶液中的气泡合并
Bubble coalescence in worm-like micellar solutions
论文作者
论文摘要
水溶液中的表面活性剂在存在盐的情况下会自组装，形成长而柔软的蠕虫状胶束（WLM）。 WLM溶液具有粘弹性特性，并用于许多应用中，例如化妆品，减速和液压压裂。 WLM溶液中气泡的动力学是许多这些产品稳定性的重要考虑因素。在此手稿中，我们研究了WLM溶液中气泡结合的薄膜引流动力学。选择了盐和表面活性剂类型和浓度，以使测试的WLM溶液的粘弹性在模量和松弛时间的两个数量级上跨越了两个数量级。排水和聚结的各个阶段 - 顶点处厚区域的形成 - 凹坑，该凹痕的稀疏和冲洗和破裂前排水的最终阶段，通过蠕虫状胶束溶液的粘弹性进行了修改。由于WLM溶液的独特粘弹性特性，我们还观察到在排水过程中的许多有趣的流体动态现象，包括弹性后坐力，薄膜撕裂和单步末端排水。
Surfactants in aqueous solutions self-assemble in the presence of salt, to form long, flexible worm-like micelles (WLM). WLM solutions exhibit viscoelastic properties and are used in many applications, such as for cosmetic products, drag reduction and hydraulic fracturing. The dynamics of bubbles in WLM solutions are important considerations for the stability of many of these products. In this manuscript, we investigate the thin film drainage dynamics leading up to the coalescence of bubbles in WLM solutions. The salts and surfactant type and concentrations were chosen so as to have the viscoelastic properties of the tested WLM solutions span over two orders of magnitude in moduli and relaxation times. The various stages in drainage and coalescence - the formation of a thick region at the apex - a dimple, the thinning and washout of this dimple and the final stages of drainage before rupture, are modified by the viscoelasticity of the wormlike micellar solutions. As a result of the unique viscoelastic properties of the WLM solutions, we also observe a number of interesting fluid dynamic phenomena during the drainage process including elastic recoil, thin film ripping and single-step terminal drainage.
