Self-organized criticality in micro- and nano-flow field generations

2019 Fiscal Year Final Research Report

• Project/Area Number: 18K18825
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 19:Fluid engineering, thermal engineering, and related fields
• Research Institution: Osaka University
• Principal Investigator: Doi Kentaro 大阪大学, 基礎工学研究科, 准教授 (20378798)
• Co-Investigator(Kenkyū-buntansha): 川野 聡恭 大阪大学, 基礎工学研究科, 教授 (00250837)
• Project Period (FY): 2018-06-29 – 2020-03-31
• Keywords: 分子流体力学 / 電気流体力学 / イオン電流 / イオンクロマトグラフィ

Outline of Final Research Achievements

Macroscopic liquid flows, which are driven by applying external forces, are based on the interactions of atoms and molecules from the microscopic viewpoint. Especially in an electrolyte solution inside a microchannel, an electrolyte solution in which an electroneutral condition is broken can be generated; electrostatic force is applied to electrolyte ions by applying an electric voltage; as a result, the surrounding solvent is dragged by the electrophoretic transport. In this study, in order to elucidate the mechanism of such a microscopic-scale flow, an experimental method for applying a directed force to a liquid by utilizing the ions in an electrolyte solution filled in a microchannel was proposed and evaluated. An ion diode was developed using a glass capillary, and selective ion transport was confirmed.

Free Research Field

分子流体力学

Academic Significance and Societal Importance of the Research Achievements

流体の駆動力として，圧力差を利用する方法が一般的に知られているが，マイクロ・ナノ流路を用いる場合は，圧力差だけでなく体積力による駆動も有効な手段として提案されている．本研究では，マイクロ流路内部の電解質溶液に陽イオンが集中した場を生成し，そこに強い電場を印加してイオンの輸送を整流した．これにより，陽イオンまたは陰イオンの選択的透過性が実現し，液体に対して一方向の体積力を加えることができ，微小空間における流体の駆動力として利用することが可能となる．マイクロ・ナノ流路における送液技術として発展が期待される．