On the flow-induced sound and vibration of elastic bodies and its active control by means of smart materials

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K13691
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 19010:Fluid engineering-related
• Research Institution: Toyama Prefectural University
• Principal Investigator: Terashima Osamu 富山県立大学, 工学部, 准教授 (50570751)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 空力騒音 / 空力振動 / 渦構造 / スマートマテリアル / 磁気応答性エラストマ / PVDF

Outline of Final Research Achievements

To elucidate the generation mechanism of flow-induced noise and vibration in elastic bodies, different types of elastic bodies were installed in a uniform flow of a wind tunnel. Subsequently, the noise and vortex structures generated around it were investigated. Furthermore, the noise was generated slightly upstream from the downstream edge of the elastic body. At this position, vibration occurs as the edge was rolled up and down, and noise with high directivity was generated in the direction perpendicular to the surface of the elastic body. We also fabricated a prototype of a vibration control device using soft smart materials, i.e., a magneto-rheological　elastomer and PVDF, and investigated its vibration mitigating effect. Additionally, we proposed control algorithms for the device.

Free Research Field

流体工学

Academic Significance and Societal Importance of the Research Achievements

これまで明らかとされていなかった流体中の弾性体の振動原理を、弾性体周囲の流れ場と発生する振動や音との関係から明らかにした。これにより、鳥類や昆虫、植物などが有する軟体部が風に曝された際に、どのように風の影響を回避しながら生息しているかを知るための一つの知見になったと考えられる。また、スマートマテリアルを利用した制御技術は、軽量・低消費電力の下に効果的に振動を制御できる可能性があるため、今後の産業界での利用が期待される。