News and Events

活動資訊

Seminar - Boundary Layer Transition Talk Series “Basic Issues of Laminar Flow Control for High-Speed Boundary-Layer Flows” by Professor Alexander V. Fedorov
日期:2018 年 08 月 07 日 ( 星期二)
Time:11:00 am – 12:00 pm
Venue:AG710

Abstract:

Although laminar-turbulent transition (LTT) is not fully understood, this does not deter the transition study community from attempting to control the LTT process. The majority of laminar-flow-control (LFC) techniques are focused on stabilizing of the boundary-layer flow. This lecture addresses key issues relevant to developments of stability modifiers in order to increase the laminar run in the boundary layer at supersonic speeds. The discussion is mainly focused on slender configurations assuming that their surface is smooth and the free stream is sufficiently quiet. In such ‘clean’ cases, the initial stage of transition is associated with excitation and downstream propagation of unstable disturbances and, therefore, the linear stability theory (LST) is a major tool for LFC developments.

In this framework, we discuss the following LFC techniques: global shaping of the body surface; stabilization of the second mode using porous coatings, CO2 injection and a wavy wall or periodic roughness elements. In connection with 3-D boundary-layer flows, we briefly discuss the method of distributed roughness elements suggested by William Saric to delay cross-flow dominated transition.

Bio-sketch:

Professor Alexander V. Fedorov is a leading researcher of Central Aerohydrodynamic Institute (TsAGI) and Associate Professor of Moscow Institute of Physics and Technology. He received his Ph.D. degree of Fluid, Gas and Plasma Dynamics form Moscow Institute of Physics and Technology in 1982. His current research interests focus on theoretical and computational modeling of stability and laminar-turbulent transition of compressible boundary-layer flows and laminar flow control. He has been in close collaboration with the Rockwell International Science Center (at present Teledyne Scientific and Imaging Company, Thousand Oaks CA) over 10 years. He also has been collaborated with the AFOSR/NASA National Center for Hypersonic Research in Laminar-Turbulent Transition, Graduate Aeronautical Laboratories of California Institute of Technology. He has published more than 150 papers and now his citations are 2479 according to google scholar. As a well-recognized scholar in the fluid dynamics, he has been awarded as Associate Fellow of the American Institute of Aeronautics and Astronautics. He received Zhukovsky Prize on Fundamental Research, TsAGI in 2006 and 2017.