Study of sound wave irradiation method to a bubble cloud by ultrasound phased array

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K14073
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 19010:Fluid engineering-related
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Sugita Naohiro 東京工業大学, 科学技術創成研究院, 助教 (80852318)
• Project Period (FY): 2021-04-01 – 2023-03-31
• Keywords: 超音波 / マイクロバブル / 気泡振動 / 音響散乱 / 超音波イメージング

Outline of Final Research Achievements

For the field of ultrasound treatment and diagnosis technology utilizing microbubbles, we proposed a sound irradiation method with a single-frequency ultrasound to induce multiple vibration responses within a bubble cloud. Through a combination of numerical analysis and experimental validation, we established the underlying principle. To achieve this, we employed a technique where the polarity of the voltage applied to each element of the ultrasonic linear array was selectively reversed. This manipulation led to the formation of distinct spatial patterns in the irradiated sound waves. By varying the irradiation patterns, we observed changes in the vibration modes exhibited by the bubble cloud.The intensity and spatial distribution of the scattered sound field were altered accordingly.

Free Research Field

超音波，気泡力学，キャビテーション，非線形力学

Academic Significance and Societal Importance of the Research Achievements

マイクロバブルの音響イメージングにおいて、本手法は気泡群の振動を効果的に利用する物理的手法である点に有用性がある。従来の非線形性を利用した画像化手法とは異なり、機序となる基礎物理が線形振動であること、さらに超音波ビームとの連成力学モデルから有効性を示したことの学術的意義は大きい。装置構成、データ処理ともに単純であり、従来の超音波診断装置をベースとした開発が期待できる点に社会的意義がある。