Development of measurement techniques for liquid-film dynamics during foam formation and collapse

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K20420
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0301:Mechanics of materials, production engineering, design engineering, fluid engineering, thermal engineering, mechanical dynamics, robotics, aerospace engineering, marine and maritime engineering, and related fields
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: Saito Shimpei 国立研究開発法人産業技術総合研究所, エネルギー・環境領域, 研究員 (80909606)
• Project Period (FY): 2021-08-30 – 2024-03-31
• Keywords: 泡沫 / 界面活性剤 / 光ファイバプローブ / 液膜 / 泡

Outline of Final Research Achievements

We have developed visualization and measurement techniques to clarify the microscopic and transient behavior of foams and their macroscopic characteristics. We constructed a two-dimensional observation system by generating foams flow on a parallel plate, and were able to clarify the conditions under which the flow phase of bubbles transitions from a dry state to a wet state. Furthermore, we constructed a measurement system for the gas-liquid interface using an optical fiber probe, and succeeded in capturing the foam-specific signal, in which the foam film (liquid phase) and the bubble (gas phase) come into contact with the fiber tip in a short time, with a high temporal resolution of less than 10 us.

Free Research Field

混相流

Academic Significance and Societal Importance of the Research Achievements

本研究は，泡沫の構造を精緻に捉えるために平行平板間に泡沫を流動させることで2次元的な泡沫の運動をその場で直接観察するとともに，光ファイバプローブによる光学的な気液界面の計測技術を泡沫に適用し，泡沫特有の信号をとらえた。本研究の成果は，極めて複雑で多様な様相を見せる泡沫の「特性理解」の一助となる学術基盤であり，可視化と光学技術を組み合わせることでこれを実現しうることを示した点にある。