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Title: Aeroacoustics of Silent Owl Flight
The ability of some species of owl to fly in effective silence is unique among birds and provides a distinct hunting advantage, but it remains a mystery as to exactly what aspects of the owl and its flight are responsible for this dramatic noise reduction. Crucially, this mystery extends to how the flow physics may be leveraged to generate noise-reduction strategies for wider technological application. We review current knowledge of aerodynamic noise from owls, ranging from live owl noise measurements to mathematical modeling and experiments focused on how owls may disrupt the standard routes of noise generation. Specialized adaptations and foraging strategies are not uniform across all owl species: Some species may not have need for silent flight, or their evolutionary adaptations may not be effective for useful noise reduction for certain species. This hypothesis is examined using mathematical models and borne out where possible by noise measurements and morphological observations of owl feathers and wings.  more » « less
Award ID(s):
1805692 1846852 0965248
PAR ID:
10156774
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Annual Review of Fluid Mechanics
Volume:
52
Issue:
1
ISSN:
0066-4189
Page Range / eLocation ID:
395 to 420
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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