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Accession Number N20120012533
Title Blade Displacement Measurement Technique Applied to a Full-Scale Rotor Test.
Publication Date May 2012
Media Count 24p
Personal Author A. I. Abrego A. W. Burner D. A. Barrows E. A. Romander L. E. Olson
Abstract Blade displacement measurements using multi-camera photogrammetry were acquired during the full-scale wind tunnel test of the UH-60A Airloads rotor, conducted in the National Full-Scale Aerodynamics Complex 40- by 80-Foot Wind Tunnel. The objectives were to measure the blade displacement and deformation of the four rotor blades as they rotated through the entire rotor azimuth. These measurements are expected to provide a unique dataset to aid in the development and validation of rotorcraft prediction techniques. They are used to resolve the blade shape and position, including pitch, flap, lag and elastic deformation. Photogrammetric data encompass advance ratios from 0.15 to slowed rotor simulations of 1.0, thrust coefficient to rotor solidity ratios from 0.01 to 0.13, and rotor shaft angles from -10.0 to 8.0 degrees. An overview of the blade displacement measurement methodology and system development, descriptions of image processing, uncertainty considerations, preliminary results covering static and moderate advance ratio test conditions and future considerations are presented. Comparisons of experimental and computational results for a moderate advance ratio forward flight condition show good trend agreements, but also indicate significant mean discrepancies in lag and elastic twist. Blade displacement pitch measurements agree well with both the wind tunnel commanded and measured values.
Keywords Aerodynamic loads
Displacement measurement
Full scale tests
Rotary wing aircraft
Shafts(Machine elements)
Wind tunnel tests

Source Agency National Aeronautics and Space Administration
NTIS Subject Category 51A - Aerodynamics
51C - Aircraft
Corporate Author National Aeronautics and Space Administration, Moffett Field, CA. Ames Research Center.
Document Type Conference proceedings
Title Note N/A
NTIS Issue Number 1303
Contract Number NNL04AA03

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