Plenary Lecture

Acoustic Excitation of Disturbances in a Supersonic Boundary Layer

Professor Sergey A. Gaponov
Khristianovich Institute of Theoretical and Applied Mechanics (ITAM)

Abstract: Present paper is devoted to those acoustical problems which are also related to the problem of the turbulence onset in high-speed boundary layers. Basic equations governing linear development of both hydrodynamic and acoustic waves in high-speed boundary layers are presented. Results of the theoretical investigation on external acoustic wave influence on the flat plate boundary layer are described. The intensity of disturbances excited by an acoustic wave inside the boundary layer has been studied. It has been found that interaction of sound with the boundary layer lead to an increase of the amplitude of disturbances inside the boundary. It has been shown that the amplitude of fluctuations inside the boundary layer may exceed the amplitude of the external acoustic field in many times. It was noted therein that there exists a region of an efficient receptivity of the sound waves in a boundary layer between the lower branch of the neutral stability curve and the leading edge. There is the continuous degeneration of an incident sound wave into a “Tollmien-Schlichting” wave in this region. On the other hand, experimentally it was found that more intense oscillations are observed in this region. With increase of the Mach number fluctuations in a layer are increased. Within the framework of a problem about interaction of acoustic waves with a boundary layer we will consider influence of stationary Mach waves on flow parameters in a supersonic boundary layer. Linear generation of internal vortex waves by external sound waves is the most efficient in regions of: the neutral curve, low Reynolds number (closing of its phase velocity). Besides in the paper nonlinear generation of increasing perturbations by acoustics is studied.

Brief Biography of the Speaker: Sergey Gaponov graduated from the Physics Department of Novosibirsk State University, Russia in 1964. With 1965 till April he works in the Khristianovich Institute of Theoretical and Applied Mechanics of Siberian Branch of Russian Academy of Science as Junior and Senior Scientific Researcher, Head of Laboratory. Now he is Main researcher of the same Institute. With 1992 he works also as Professor of the Department of Theoretical Mechanics, Novosibirsk State University of Architecture and Civil Engineering. S. Gaponov is the expert in a field of the fluid and gas mechanics. The basic directions of his scientific activity are connected with researches of hydrodynamic stability, non-stationary processes and the turbulence occurrence in supersonic gas flows. He defended the candidate thesis "Stability of the incompressible boundary layer on a permeable Surface" (1971) and doctor thesis (physics and mathematics) “Development of disturbances in a supersonic boundary layer” (1987). He is member of Council on a defence of doctoral theses at Institute of Theoretical and Applied Mechanics, member of Russian National Committee on Theoretical and Applied Mechanics, member of the International Scientific Committee on Fluid Mechanics and Aerodynamics. The prize of Zhukovsky was awarded to him. There are many grants for fundamental research in which he took part: Grant of International Science and Technology Center: ISTC-128-96 investigator, Grants of Russian Foundation for Basic Research (team leader.) He took part in work of numerous scientific conferences, including the Fluid Mechanics and Aerodynamics conferences. Number of his papers in refereed journals is more than160. Three books were published.

Bulletin Board


The Conference Guide is online.

The paper submission deadline has expired. Please choose a future conference to submit your paper.

Plenary Speakers

WSEAS Main Site

Publication Ethics and Malpractice Statement