Active Load Control for Airfoils using Microtabs

[+] Author and Article Information
D. T. Yen Nakafuji

New Technologies Engineering Division, Lawrence Livermore National Laboratory, P.O. Box 808, L-644, Livermore, CA 94551e-mail: nakafuji2@llnl.gov

C. P. van Dam

Department of Mechanical and Aeronautical Engineering, University of California at Davis, Davis, CA 95616e-mail: cpvandam@ucdavis.edu

R. L. Smith, S. D. Collins

Department of Electrical and Computer Engineering, University of California at Davis, Davis, CA 95616

J. Sol. Energy Eng 123(4), 282-289 (Jul 01, 2001) (8 pages) doi:10.1115/1.1410110 History: Received December 01, 2000; Revised July 01, 2001
Copyright © 2001 by ASME
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Grahic Jump Location
Translational microtab concept: a) Conventional versus translational microtab approach, b) predicted effect of microtab extension on lift
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Process flow for dovetail design used in microtabs
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Three-piece tab assembly consisting of a base, slider, and extender in a modular track assembly. Tab shown in 2-position ON (extended) and OFF (retracted) operation on airfoil pressure side.
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Comparison of present experimental results and computed Reynolds-averaged Navier-Stokes results (INS2D) with previously published results for the baseline airfoil at Re=0.63×106 and transition fixed at xtrans/c=0.455
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Computed streamlines based on Reynolds-averaged Navier-Stokes (INS2D) solution for airfoil with tab (h/c=0.01) at α=0°,Re=1.0×106,xtrans/c=0.455
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Computed surface pressure distributions data for baseline airfoil and airfoil with tabs (h/c=0.01) at the trailing edge and 5% from the trailing edge at α=0°,Re=1.0×106,xtrans/c=0.455
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Test model as mounted in the UC Davis Wind Tunnel Facility
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Wind tunnel testing process flow
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Comparison of present results and previously published results (Glasgow) for baseline airfoil at Re=0.63×106, boundary-layer trip at xtrans/c=0.455
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Installation of a) fixed tab at 10% from the trailing edge and b) remotely activated microtabs at 5% from the trailing edge
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a) Effect of tab height (tab at 5% from trailing edge) and b) effect of tab location (nominal tab height of 1%) on force coefficients for airfoil at α=0°,Re=1.0×106,xtrans/c=0.455
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Comparison of experimental and computed tab lift effectiveness at Re=1.0×106,xtrans/c=0.45. Tab at 5% from trailing edge with nominal tab height of 1%.
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Comparison of experimental and computed a) pitching moment coefficient and b) drag polar at Re=1.0×106,xtrans/c=0.455. Tab at 5% from trailing edge with nominal tab height of 1%
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Measured a) tab height effect (tab at 5% from trailing edge) and b) tab location effect (tab height of h/c=0.011) on lift coefficient at Re=1.0×106,xtrans/c=0.455
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Comparison of fixed (solid) tab effect and remotely activated tab (tab spacing s/h=0.5) effect of lift coefficient at Re=1.0×106,xtrans/c=0.455. Tabs at 5% from trailing edge with nominal tab height of 1%.




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