Boundary-layer receptivity of sound with roughness
Academic Article
Overview
Overview
abstract
Boundary-layer receptivity was investigated using an acoustical disturbance in the freestream. A uniform two-dimensional roughness strip provided the mechanism to enhance the receptivity. The roughness element provided the site for local adjustment in the boundary layer required to convert the long-wavelength acoustical disturbance to the short-wavelength Tollmien-Schlichting (T-S) wave. Small changes in the forcing frequency or the height of roughness element produced large changes in the amplitude of the observed T- S wave. (D.W.T.)
