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  • Single degree of freedom vortex induced vibration of undulatory seal whiskers at low Reynolds number and various angles of attack: A computational fluid dynamics study

This content will become publicly available on September 1, 2025

Title: Single degree of freedom vortex induced vibration of undulatory seal whiskers at low Reynolds number and various angles of attack: A computational fluid dynamics study
The cross-flow vortex-induced vibration (VIV) response of an elastically mounted idealized undulatory seal whisker (USW) shape is investigated in a wide range of reduced velocity at angles of attack (AOAs) from 0° to 90° and a low Reynolds number of 300. The mass ratio is set to 1.0 to represent the real seal whisker. Dynamic mode decomposition is used to investigate the vortex shedding mode in various cases. In agreement with past studies, the VIV response of the USW is highly AOA-dependent because of the change in the underlying vortex dynamics. At zero AOA, the undulatory shape leads to a hairpin vortex mode that results in extremely low lift force oscillation with a lowered frequency. The frequency remains unaffected by VIV throughout the tested range of reduced velocity. As the AOA deviates from zero, alternating shedding of spanwise vortices becomes dominant. A mixed vortex shedding mode is observed at AOA = 15° in the transition. As the AOA deviated from zero, the VIV amplitude increases rapidly by two orders, reaching the maximum of about 3 times diameter at 90°. An infinite lock-in branch is present for AOA from 60° to 90°, where the VIV amplitude remains high regardless of the increase in reduced velocity.  more » « less
Award ID(s):
2327204
PAR ID:
10570438
Author(s) / Creator(s):
; ;
Publisher / Repository:
AIP Publishing
Date Published:
Journal Name:
Physics of Fluids
Volume:
36
Issue:
9
ISSN:
1070-6631
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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