Study on flow-indueed structure and instability of surfactant aqueous solution by measuring microscopic distribution of flow birefringence

通过测量流动双折射的微观分布研究表面活性剂水溶液的流动致结构和不稳定性

• 批准号: 15560133
• 负责人: TAKAHASHI Tsutomu
• 金额: $ 2.37万
• 依托单位: Nagaoka University of Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15560133/
• 关键词: surfactant aqueous solution; shear-induced structure; flow birefringence; micelles structure; flow instability; wormlike micelles; 流動有機構造変化; 流動不安定性

This research is an investigation of flow property of surfactant aqueous to use as working fluid. We introduced a microscopic point of view into this research with considering the flow-induced structure change of micelles. Prof.Shikata, Osaka University, reported that the wormlike micelles are not only entangled but they are passing through each other. Since we thought that the micelles aligned stronger than polymer filaments by this concept, we measured the state of alignment of micelles by flow birefringence. Moreover, we aimed to develop the birefringence distribution microscope metrology that was able to measure the distribution of the flow birefringence from several μm at tens of μm intervals, and to measure the process from the change in the micelle that formed the texture structure such as banding to the generation of unstable flow by the resolution of the optical microscope order. The flow behavior of a surfactant solution, CTAB/NaSal, in parallel plates flow cell which has 0.5 … More mm to 2.0mm in gap was observed by using optical microscope. To make start-up flow with a constant flow rate, a syringe pump was used. It was observed by the flow visualization that all sample in the flow cell becomes opaque immediately after beginning of flow when the flow rate exceeds a certain value. In this case, the shear stress and strain applied homogeneously to the sample in the flow cell and then the shear induced two opaque thin layers formed near the upper and lower plates. After a while, a white band area which is orthogonal to the flow direction is formed on the entrance region. This band area is also the micelle's structure change but it is generated by elongation deformation in reservoir. The nonuniformity of this band area causes instability of flow. The instrument which can measure the flow birefringence at different 16 positions simultaneously was completed. By using this instrument, the start-up behavior of the distribution of the flow birefringence in the flow cell was measured. Less

本研究系以表面活性剂水溶液为工质，探讨其流动特性。我们引入微观的观点，考虑到流动引起的胶束结构变化的研究。大坂大学的Shikata教授报告说，蠕虫状胶束不仅纠缠在一起，而且它们还相互穿过。由于我们认为胶束的排列比聚合物长丝更强，因此我们通过流动双折射测量胶束的排列状态。此外，我们还开发了能够以数十μm的间隔测量从数μm开始的流动双折射分布的双折射分布显微镜计量，并通过光学显微镜级的分辨率测量从形成织构结构（如条带）的胶束的变化到产生不稳定流动的过程。研究了表面活性剂CTAB/NaSal溶液在平行板流动池中的流动行为， ...更多信息 通过光学显微镜观察到间隙在2.0mm至2.0mm之间。为了以恒定流速进行启动流动，使用注射泵。通过流动可视化观察到，当流速超过一定值时，流动池中的所有样品在流动开始后立即变得不透明。在这种情况下，剪切应力和应变均匀地施加到流动池中的样品，然后剪切诱导在上板和下板附近形成两个不透明的薄层。一段时间后，在入口区域上形成与流动方向正交的白色带区域。该条带区也是胶束的结构变化，但它是由储层中的伸长变形产生的。该带区域的不均匀性导致流动的不稳定性。研制了一台能同时测量16个不同位置的流体双折射的仪器。利用该仪器测量了流动池中流体双折射分布的启动行为。少