2021 Fiscal Year Final Research Report

Measurement of unsteady flow generated by deformable object for understanding locomotion principle

Research Project

PDF

Project/Area Number	19H00800
Research Category	Grant-in-Aid for Scientific Research (A)
Allocation Type	Single-year Grants
Section	一般
Review Section	Medium-sized Section 24:Aerospace engineering, marine and maritime engineering, and related fields
Research Institution	Tohoku University
Principal Investigator	Asai Keisuke 東北大学, 工学研究科, 教授 (40358669)
Co-Investigator(Kenkyū-buntansha)	青野光信州大学, 学術研究院繊維学系, 准教授 (10623712) 齋藤勇士東北大学, 学際科学フロンティア研究所, 助教 (50828788) 野々村拓東北大学, 工学研究科, 准教授 (60547967) 小澤雄太東北大学, 工学研究科, 助教 (10898290) 澤田惠介東北大学, 工学研究科, 教授 (80226068)
Project Period (FY)	2019-04-01 – 2022-03-31
Keywords	感圧塗料 / 変形計測 / 回転翼 / 羽ばたき翼 / ロコモーション原理
Outline of Final Research Achievements	The purpose of this study was to clarify the aerodynamic mechanism of locomotion caused by unsteady flow forces on a moving wing surface and to establish the experimental methods necessary for this purpose. By combining a pressure-sensitive paint (PSP) consisting of dye molecules having oxygen quenching properties with a lifetime measurement method and three-dimensional deformation measurement (VDM) using data assimilation, we developed a technique to image unsteady pressure distribution on a deforming wing surface and demonstrated its effectiveness in the benchmark experiments on a rotating wing and a flapping wing. Using the newly-developed techniques, we investigated the relationship between the large-scale separation vortex and the hydrodynamic forces acting on the wing surface, and obtained many insights into the mechanism by which a moving wing surface generates lift and thrust, paving the way to solving design problems that could not be solved by theory alone.
Free Research Field	航空宇宙工学
Academic Significance and Societal Importance of the Research Achievements	運動する翼面の周囲には前縁剥離渦や渦輪などの大規模な剥離渦が存在し，それらと翼面との相互作用で生まれる流体力が外乱に対するロバスト性を生んでいる．回転翼や羽ばたき翼を有する飛行ロボットは社会における様々な分野での利用だけでなく，火星などの大気を有する天体の探査計画への適用が期待されている．様々な大気条件下における安定した飛行を保証するには，大規模剥離渦と翼面に働く流体力の関係を調べる先進的な実験手法の確立が不可欠であり，本研究で得られた技術と知見は，運動を伴う翼面の非定常流体力によるロコモーションの空気力学的メカニズムの解明だけでなく，様々な形態の飛行機械の設計指針の確立に寄与するものである．