Quantitative analysis of vortex generation, development and decay processes, and its application to highly efficient wall turbulence control

2023 Fiscal Year Final Research Report

• Project/Area Number: 21H01245
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 19010:Fluid engineering-related
• Research Institution: Tokyo University of Agriculture and Technology
• Principal Investigator: Iwamoto Kaoru 東京農工大学, 工学(系)研究科(研究院), 教授 (50408712)
• Co-Investigator(Kenkyū-buntansha): 光石 暁彦 大阪電気通信大学, 工学部, 准教授 (90456715) ; 仁村 友洋 東京農工大学, 工学(系)研究科(研究院), 特任助教 (90982603)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 壁乱流 / 渦 / 輸送方程式 / 直接数値計算 / 乱流制御

Outline of Final Research Achievements

Life cycle of vortices, which are core structures of wall turbulence, was quantitatively elucidated including generation, development, and decay processes using a newly derived transport equation for vortical structures. Specifically, direct numerical simulations of turbulent channel flow were performed using a high-resolution spectral method, and the characteristics of each term in the transport equation were clarified. Furthermore, by using the vortex transport equation, we focused on the temporal evolution of vortices, which could not be taken into account in the past, and developed a more efficient turbulence control law.

Free Research Field

流体工学

Academic Significance and Societal Importance of the Research Achievements

本研究では，壁乱流の中核的構造である渦の生成・発達・消滅過程を定量的に世界で初めて明らかにし，渦構造の普遍的知見を得た．新規に導出した渦の輸送方程式は，抵抗低減を目的とした乱流制御に留まらず，渦に関連する全ての流体現象に応用が可能である．即ち剥離や流れ構造の制御，流体力の制御，騒音低減，伝熱・拡散制御，反応制御などにも適用でき，新技術開発，環境問題軽減に貢献できる．