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  • Accepted Manuscript: Effect of Structural Modifications on Vibratory Response of Panel under Ramp-Induced Shock Wave Boundary Layer Interaction
Title: Effect of Structural Modifications on Vibratory Response of Panel under Ramp-Induced Shock Wave Boundary Layer Interaction
The vibration of a compliant panel under a shock / boundary layer interaction (SBLI) induced by a compression ramp in a Mach 2 flow, is investigated experimentally. The panel is made from brass shim stock of length (streamwise), width (spanwise) and thickness of 122 mm by 63.5 mm by 0.25 mm, respectively. The 20° compression ramp is placed near the downstream edge of the compliant panel, and it creates a shock-induced turbulent separated flow that extends over the downstream 20% of the panel. Large pressure fluctuations occur in the region of the separation shock foot unsteadiness. The pressure fluctuations increase vibration amplitudes of the higher panel modes, especially the second mode, which has an antinode near the shock foot region. In this work, the authors use structural modifications of the baseline compliant panel to mitigate vibrations induced by the large pressure fluctuations of the shock foot unsteadiness. A thin rib is attached in the spanwise direction to the lee side of the panel at the location of SBLI. In one configuration, the rib is attached to the panel using epoxy adhesive, which creates a stiff connection. In another configuration, the rib is attached to the panel via double-sided viscoelastic tape, more » which adds significant damping to the system. The panel vibration and surface pressure field are measured using stereoscopic digital image correlation and pressure sensitive paint. Results show that especially the second vibration mode of the panel is reduced through the addition of the rib. This effect is more pronounced in the case where the viscoelastic tape was used, where a 72% reduction in vibration is observed. « less
Authors:
; ; ; ;
Award ID(s):
1913587
Publication Date:
NSF-PAR ID:
10357644
Journal Name:
AIAA Scitech Meeting
Sponsoring Org:
National Science Foundation
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