University of Maryland DRUM  
University of Maryland Digital Repository at the University of Maryland

Digital Repository at the University of Maryland (DRUM) >
Theses and Dissertations from UMD >
UMD Theses and Dissertations >

Please use this identifier to cite or link to this item: http://hdl.handle.net/1903/7802

Title: Comparison Of Free-Vortex Wake Models For A Sub-Scale Rotor At Low Speeds
Authors: Roark, Sean
Advisors: Leishman, Gordon
Department/Program: Aerospace Engineering
Type: Thesis
Sponsors: Digital Repository at the University of Maryland
University of Maryland (College Park, Md.)
Subjects: Engineering, Aerospace
Issue Date: 10-Dec-2007
Abstract: During shipboard testing in 1999, the V-22 Osprey tiltrotor experienced two separate uncommanded roll events as a result of an upwind-generated helicopter rotor wake, entrained in the ship's airwake, impinging upon its rotors. A portion of this thesis documents the author's involvement in one of the resulting wind tunnel tests created to investigate these events. The remainder details the attempts to validate the Maryland Free Wake (MFW) and Continuum Dynamics' CHARM free-vortex wake models using that low speed wind tunnel data. Results presented in this thesis show while the models qualitatively predict the downstream wake structure, they exhibit some interesting behavior in the far wake that is not in agreement with the measurements. To improve the correlation, changes to rotor parameters and the wake growth parameter were made, but with limited success. Potential explanations for the behavior are given, and recommendations for future research are also discussed.
URI: http://hdl.handle.net/1903/7802
Appears in Collections:UMD Theses and Dissertations
Aerospace Engineering Theses and Dissertations

Files in This Item:

File Description SizeFormatNo. of Downloads
umi-umd-5085.pdf52.16 MBAdobe PDF631View/Open

All items in DRUM are protected by copyright, with all rights reserved.

 

DRUM is brought to you by the University of Maryland Libraries
University of Maryland, College Park, MD 20742-7011 (301)314-1328.
Please send us your comments