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Title: Unsteadiness in Shock/Boundary-Layer Interaction Over a Compliant Panel at Mach 2
This work investigates surface pressure unsteadiness on a compliant panel under a shockwave/boundary-layer interaction (SBLI) induced by a 2D compression ramp with an angle of 20o in a Mach 2 wind tunnel. High-speed digital image correlation (DIC) and fast-response pressure-sensitive paint (PSP) measurements are used to measure the panel displacement and panel and ramp-face surface pressure fluctuations at 5kHz and 20kHz, respectively. The data reduction technique of POD (proper orthogonal decomposition) was employed both for pressure and displacement fields. POD mode distribution for the pressure fields reveals that the first six modes have 60% of the total energy and exhibit low-frequency content for both rigid and compliant panels. The vibration of the compliant panel was seen to alter the energy distribution of the high energy modes as compared to the rigid panel case. The cross-correlations between the displacement and pressure modes were made using the time coefficients. This analysis shows significant correlations were present among the lower modes. The highest correlation was between displacement mode 1 and the pressure mode 4, which stemmed from the upstream of the intermittent region. The analysis was also made for the surrogate shock foot and reattachment lines. The correlation shows that panel vibration lowers the correlation between the shock foot and reattachment line when compared with the rigid panel case.  more » « less
Award ID(s):
1913587
NSF-PAR ID:
10357646
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
AIAA Aviation Meeting
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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