Department News
Development of Low-Frequency Streaks in Boundary Layers
Seminar Date
2004-01-26
Author
안지영
Date
2004-01-26
Views
1642
1. 제 목 : Development of Low-Frequency Streaks in Boundary Layers
2. 연 사 : Dr. A. V. Boiko
Senior Research Scientist, Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia Also, Visiting Professor at ASERC, Pusan National University
3. 일 시 : 2004년 1월 31일(토) 오전 11시
4. 장 소 : 301동 1512호 세미나실
5. 내 용 : The presentation is devoted to a response of flat plate and swept wing boundary layers to a single free stream quasi-stationary axial vortex of limited spanwise extent is investigated. On the flat plate the response is dominated by a streamwise velocity perturbation (streak), whose characteristics are in agreement with data of previous experiments performed with natural streaks developed under effect of free stream turbulence. A quantitative comparison of the observed streak characteristics with available theoretical approaches is performed. On the swept wing the response is dominated by stream-wise velocity perturbations, that grew quasi-exponentially over the model. It is shown that the disturbance transformation on the swept wing occurs close to the leading edge followed by formation of a wave packet with characteristic specific for cross-flow instability. Meanwhile, disturbances, which can be attributed to the streaks are also identified.
6. 문 의 : 기계항공공학부 최 해 천 교수 (☏ 880-8361)
2. 연 사 : Dr. A. V. Boiko
Senior Research Scientist, Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russia Also, Visiting Professor at ASERC, Pusan National University
3. 일 시 : 2004년 1월 31일(토) 오전 11시
4. 장 소 : 301동 1512호 세미나실
5. 내 용 : The presentation is devoted to a response of flat plate and swept wing boundary layers to a single free stream quasi-stationary axial vortex of limited spanwise extent is investigated. On the flat plate the response is dominated by a streamwise velocity perturbation (streak), whose characteristics are in agreement with data of previous experiments performed with natural streaks developed under effect of free stream turbulence. A quantitative comparison of the observed streak characteristics with available theoretical approaches is performed. On the swept wing the response is dominated by stream-wise velocity perturbations, that grew quasi-exponentially over the model. It is shown that the disturbance transformation on the swept wing occurs close to the leading edge followed by formation of a wave packet with characteristic specific for cross-flow instability. Meanwhile, disturbances, which can be attributed to the streaks are also identified.
6. 문 의 : 기계항공공학부 최 해 천 교수 (☏ 880-8361)
