Abstract
Simultaneous planar laser imaging and fluctuating pressure measurements have been made for a rectangular cavity in a Mach 5 flow. Results are presented in the form of instantaneous side-view images, fluctuating pressure signals (on the front and rear walls), and conditional-average velocity profiles across the shear-layer for a cavity length-to-depth ratio of 7. The instantaneous planar laser scattering images show no evidence for coherent structures that are induced by the cavity acoustics. Furthermore, both the pressure measurements and imaging suggest that the rear wall shock is caused by the impingement of shear-layer turbulent structures. Ensemble-average velocity profiles in the shear-layer, conditioned upon the front wall pressure, show no evidence for the deflection of the shear-layer at different phases of the oscillation cycle. These results suggest that the present cavity flow exhibits substantially less coupling between the cavity acoustics and the shear-layer fluid dynamics as compared to similar flows at lower Mach numbers.
Copyright 1999 by Ö.H. Ünalmis, N. T. Clemens, and D. S. Dolling.
Published by the American Institute of Aeronautics and Astronautics, Inc. with Permission.
Complete paper, AIAA-99-0297.