2025年度　第1回航空宇宙技術セミナー

題目

Extreme Aerodynamics: Flow Analysis and Control for Highly Gusty Conditions

平 邦彦 教授（UCLA）

UCLA機械・航空宇宙工学教授．計算およびデータ駆動型アプローチによる非定常空気力学と流体制御の研究に従事．現職に就く以前はフロリダ州立大学で教鞭をとる．テネシー大学ノックスビル校で学士号，カリフォルニア工科大学で修士号と博士号を取得．2013年AFOSR Young Investigator Award，2017年ONR Young Investigator Award，2022年DoD Vannevar Bush Faculty Fellowshipを受賞．APSフェロー，AIAAアソシエイトフェロー．現在Physical Review Fluids誌のアソシエイトエディタを務める．AIAA Journal誌およびTheoretical and Computational Fluid Dynamics誌のアソシエイトエディタを歴任．

Kunihiko Taira is a Professor of Mechanical and Aerospace Engineering at UCLA, working in unsteady aerodynamics and flow control using computational and data-driven approaches. Prior to joining his current institution, he was a faculty member at Florida State University.  He received his B.S. from the University of Tennessee, Knoxville, and his M.S. and Ph.D. from the California Institute of Technology. He is a recipient of the 2013 AFOSR Young Investigator Award, the 2017 ONR Young Investigator Award, and the 2022 DoD Vannevar Bush Faculty Fellowship.  He is a Fellow of APS and an Associate Fellow of AIAA.  He currently serves as an Associate Editor for Physical Review Fluids and has served as an Associate Editor for the AIAA Journal and Theoretical and Computational Fluid Dynamics.

2025年6月18日（水）16:00～17:30

風の強い日に小型の航空機をビルや山の風下で運用することは避けられている．本条件下では航空機が大規模構造の後流から大きい過渡的空気力を受け，飛行制御が大変困難または不可能になることがある．このような航空機周りの空気の乱れが運航速度を上まわる空気力学をExtreme Aerodynamicsと呼ぶ．従来の空気力学で考慮されている非定常性よりもはるかに高い非定常性を持つExtreme Aerodynamicsはその高次元性，非線形性，マルチスケール性のため，流れの解析と制御を困難にしている．そのため，状態変数の次元を下げ，支配的なダイナミクスを抽出できなければ，力学系や制御理論を飛行・流れ制御に応用することは難しい．本講演では，データ駆動解析や機械学習を活用してこのような複雑な流れを低次元モデル化し制御する取り組みについて紹介する．また，Extreme Aerodynamicsにおける未解決研究テーマについても議論する．

※発表はすべて英語となります.

※講演会の録画、録音等は固くお断りいたします.

An air vehicle trying to operate in adverse weather or wakes of urban canyons and mountainous terrains would be hit by strong, large-scale atmospheric disturbances.  In such extreme aerodynamic conditions, flight control becomes a great challenge, if not impossible, due to the enormous transient forces that the vehicle experiences.  Currently, encounters with these extreme flow phenomena limit operations of fixed and rotating wing aircraft, especially those that are small to medium in size.  The present study is focused on the analysis, modeling, and control of extreme aerodynamic flows, with unsteadiness far larger in amplitudes than those considered in traditional aerodynamics on a time scale comparable to those of the flow instabilities.  The high dimensionality, strong nonlinearity, and multi-scale properties of these extreme flows make systematic analysis and control a tremendous challenge.  Without the reduction of the state variable dimension and extraction of dominant dynamics, the application of dynamical systems and control theory for flight/flow control remains difficult.  This talk will present our research group’s recent efforts to model and control such complex fluid flows by leveraging data-driven techniques.  We in particular will discuss the use of unsupervised and supervised machine learning techniques and how they can be embedded in existing flow analysis techniques.  Equipped with these toolsets, we extract the essential inertial manifolds of extreme aerodynamics to facilitate the development of sparse and reduced-order models to design flow control techniques.  Some of the successes in characterizing, modeling, and controlling extreme aerodynamic flows will be presented, followed by discussions on open problems and outlooks.

※This lecture will be conducted in English.

※Recording is strictly prohibited.

国立大学法人東海国立大学機構

岐阜大学　航空宇宙生産技術開発センター/名古屋大学　フライト総合工学教育研究センター