Wagging the tail: Elasticity and flexible filaments in microscopic flows

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K03958
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 19010:Fluid engineering-related
• Research Institution: Okinawa Institute of Science and Technology Graduate University
• Principal Investigator: HAWARD SIMON 沖縄科学技術大学院大学, マイクロ・バイオ・ナノ流体ユニット, 研究員 (20812986)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: microfluidics / viscoelasticity / flow stability / cylinder

Outline of Final Research Achievements

Flow around a cylinder is a benchmark problem in non-Newtonian fluid mechanics due to its wide relevance to fundamental and applied systems. Microfluidic cylinder devices can give access to regimes of low inertia and high elasticity, which are useful in understanding viscoelastic non-Newtonian flows. But, until now, such studies have been limited by standard microfabrication methods and have mostly relied on qualitative observations. In this project, the state-of-the-art microfabrication technique of selective laser-induced etching (SLE) was used to produce microfluidic cylinder devices in new geometrical regimes. Combined with fully quantitative flow diagnostic methods, viscoelastic flows and instabilities around the new cylinder devices have been studied. The SLE fabrication method has also been used to produce microscopic flexible structures, yielding the first quantitative study of interactions between responsive, flexible filaments and non-Newtonian fluids.

Free Research Field

viscoelastic fluids

Academic Significance and Societal Importance of the Research Achievements

The research has been of interest to researchers in microfluidics, fluid mechanics, rheology, engineering and physics, and resulted in 20 papers in international peer-reviewed journals. The findings are significant for understanding viscoelastic flow instabilities and elastic turbulence.