Publication:
Jet Characteristics of a Plunging Airfoil

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Authors
Lai, J.C.S.
Platzer, M.F.
Subjects
Advisors
Date of Issue
1999
Date
1999
Publisher
AIAA
Language
en_US
Abstract
Water-tunnel tests of a NACA 0012 airfoil that was oscillated sinusoidally in plunge are described. The flowfield downstream of the airfoil was explored by dye flow visualization and single-component laser Doppler velocimetry (LDV) measurements for a range of freestream speeds, frequencies, and amplitudes of oscillation. The dye visualizations show that the vortex patterns generated by the plunging airfoil change from drag-producing wake flows to thrust-producing jet flows as soon as the ratio of maximum plunge velocity to freestream speed, i.e., the nondimensional plunge velocity, exceeds approximately 0.4. The LDV measurements show that the nondimensional plunge velocity is the appropriate parameter to collapse the maximum streamwise velocity data covering a nondimensional plunge velocity range from 0.18 to 9.3. The maximum streamwise velocity at a given streamwise distance downstream starts to exceed the freestream speed as soon as the nondimensional plunge velocity exceeds 0.25. Furthermore, this maximum jet velocity has been shown to be a linear function of the nondimensional plunge velocity.
Type
Conference Paper
Description
Presented as Paper 98-0101 at the AIAA 36th Aerospace Sciences Meeting, Reno, NV, 12–15 January 1998
The article of record as published may be found at https://doi.org/10.2514/2.641
Series/Report No
Department
Aeronautics and Astronautics
Organization
Naval Postgraduate School
Identifiers
NPS Report Number
Sponsors
Funder
Format
9 p.
Citation
Lai, J. C. S., and M. F. Platzer. "Jet characteristics of a plunging airfoil." AIAA journal 37.12 (1999): 1529-1537.
Distribution Statement
Rights
This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
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