Pumping-up tansition of high visous fluid and generation mechanism of liquid-filament under the centrifugal force field by a rotating cone

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K06066
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Fluid engineering
• Research Institution: Akita University
• Principal Investigator: Adachi Takahiro 秋田大学, 理工学研究科, 教授 (60344769)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: 回転円すい / 膜状揚水 / 糸状揚水

Outline of Final Research Achievements

When a cone is immersed in water and rotated, a filmwise flow is pumped up along the outer surface of the cone. In the case of Newtonian fluid that is more viscous than water, filament-wise pumping-up flow appears on the outer surface of the cone due to the effect of spinnability. At this time, the liquid does not scatter despite the centrifugal force acting on the pumped flow on the outer surface of the cone. We investigated the mechanism of successful formation of liquid filament-wise flow from using the transition phenomenon from filmwise pumping to filament-wise pumping. In this study, the generation conditions of the filmwise pumping and the filament-wise pumping were clarified with respect to the change of the rotation speed and the viscosity. Moreover, the value of power required for pumping was clarified.

Free Research Field

熱流体工学

Academic Significance and Societal Importance of the Research Achievements

本研究では、液糸の生成方法について研究を行なった。円すいを回転させる方法を用い、これまでとは異なる製法を用いることで、必要となる消費動力の低減にもつながる可能性を有することを見いだした。このような方法は、コロナ対策で品不足となった不織布マスクを生成することに応用できる。日本の繊維産業が急速なテンポで縮小を余儀なくされきた中で、不織布だけは確実な成長を遂げており、生活に密着した分野から工業分野にいたる幅広い分野の新用途で発展が期待できる。