Experimental Study of Controlled Disturbances Development In A supersonic Boundary Layer on A Swept Wing

摘要

The experimental results on the laminar-turbulent transition in three-dimensional boundary layers for M > 1 are described. Stationary structures were registered using different methods of flow visualization. The first experimental studies of instability of a three-dimensional boundary layer at supersonic velocities were conducted. Evolution of natural fluctuations in the boundary layer on a swept wing was studied. It was shown that the character of distribution of the mean and fluctuating characteristics of the boundary layer is similar to the case of subsonic velocities. A downstream increase in these disturbances was found in analyzing the spectra of natural fluctuations. It was obtained at M=2, flat the disturbances growth in three-dimensional boundary layer occurs much faster, than in the flat plate case. The increase of the Mach number up to 3.5 extends frequency band of amplifying disturbances and leads to earlier turbulent transition. The results of an experimental study of evolution of controlled disturbances on a swept-wing model for Mach number M=2 are presented. The wave characteristics of traveling waves are obtained. The objective of present work is an experimental study of nonlinear evolution of controlled disturbances on a swept wing supersonic boundary layer.