High Frequency Excitation for Cavity Flow Control: Combined Experiments and Linear Stability Analysis
Abstract
A rod in cross flow is a technique known for its simple and effective means of suppressing cavity tones. Although several hypotheses have been put forward regarding its working principle, no validated explanation exists. In the present study we investigate whether the cylinder, through its wake, changes the stability characteristics of the shear layer that develops over the cavity. The present study pertains to a shallow cavity of length to depth ratio L/D = 2, for subsonic Mach numbers ranging from 0.5 to 0.8. The upstream boundary layer was found to be turbulent for all cases considered. We use linear stability theory in the spatial, compressible and inviscid formulation for our study. We construct artificial velocity profiles that are prototypical of the experimentally measured velocity profiles, to investigate how the wake of the cylinder influences the stability of the shear layer. Comparison of these integrated growth rates with the acoustic suppression data showed that the link between the two is weak. Thus the ability of the rod to suppress cavity resonance is not directly explained by linear stability analysis of the modified shear layer, for the configurations considered.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 30, 2009
- Accession Number
- ADA521994
Entities
People
- Ganesh G. Raman
- Praveen Panickar
- Shekhar M. Sarpotdar
Organizations
- Illinois Institute of Technology