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Title: Scaling laws for the propulsive performance of three-dimensional pitching propulsors
Scaling laws for the thrust production and energetics of self-propelled or fixed-velocity three-dimensional rigid propulsors undergoing pitching motions are presented. The scaling relations extend the two-dimensional scaling laws presented in Moored & Quinn ( AIAA J. , 2018, pp. 1–15) by accounting for the added mass of a finite-span propulsor, the downwash/upwash effects from the trailing vortex system of a propulsor and the elliptical topology of shedding trailing-edge vortices. The novel three-dimensional scaling laws are validated with self-propelled inviscid simulations and fixed-velocity experiments over a range of reduced frequencies, Strouhal numbers and aspect ratios relevant to bio-inspired propulsion. The scaling laws elucidate the dominant flow physics behind the thrust production and energetics of pitching bio-propulsors, and they provide guidance for the design of bio-inspired propulsive systems.  more » « less
Award ID(s):
1653181
NSF-PAR ID:
10112218
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Journal of Fluid Mechanics
Volume:
871
ISSN:
0022-1120
Page Range / eLocation ID:
1117 to 1138
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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