On the development of controlled stationary and travelling disturbances in the supersonic boundary layer of a swept wing

Gleb Kolosov,Alexandra Panina,Alexander Kosinov,D Markovich,D Zaitsev,A Semenov

doi:10.1051/epjconf/201715900024

Abstract

Experimental data on the evolution of controlled stationary and travelling disturbances in a 3D supersonic boundary layer, over a 45° swept-wing at Mach number 2.0, is presented. Travelling artificial disturbances were introduced in the boundary layer by periodical glow discharge, at a frequency of 20 kHz. Stationary disturbances were acquired by setting the roughness elements on the surface of the model. Spatial-temporal and spectral-wave characteristics of the wave train at the frequency 20 kHz, in the linear region of development, were obtained. It was found that the periodic modulation of mean flow can lead to the stabilization of unstable travelling disturbances in the supersonic boundary layer of a swept wing. These experiments have investigated the viability of using roughness elements to control laminar-turbulent transition.

Highlights

The transition to turbulence in swept-wing boundary layers has been the focus of considerable attention by researchers for more than 30 years [1, 2]
The wave train is spread along the leading edge of the model in the direction opposite to the crossflow, and this is consistent with previously obtained results for the same Mach number (2.0) [11, 12]
An experimental study was conducted on the development of controlled travelling and stationary disturbances in a supersonic boundary layer of swept wing

Summary

Introduction

The transition to turbulence in swept-wing boundary layers has been the focus of considerable attention by researchers for more than 30 years [1, 2]. Modern theory on transition mechanisms in threedimensional (3D) boundary layers gives four basic types of flow instabilities: (1) attachment line boundary layer instability on the swept leading edge; (2) crossflow instability; (3) centrifugal instability; and (4) possible instability of Tollmien–Schlichting waves. Their relative roles in laminar-turbulent transition strongly depends upon a variety of factors, such as the level of free stream disturbances, surface quality, Mach number, model geometry etc

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