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Accession Number:
ADA621975
Title:
Self-sustained Flow-acoustic Interactions in Airfoil Transitional Boundary Layers
Descriptive Note:
Final performance rept. 1 Apr 2012-31 Mar 2015
Corporate Author:
EMBRY-RIDDLE AERONAUTICAL UNIV DAYTONA BEACH FL
Report Date:
2015-07-09
Pagination or Media Count:
9.0
Abstract:
This project conducted complementary experimental and numerical studies of flow-acoustic resonant interactions in transitional airfoils and their impact on airfoil surface unsteady pressure and acoustic signature. The symmetric NACA-0012 airfoil and the slightly cambered SD7003 airfoil at moderate incidence were tested in the free-jet anechoic wind tunnel of Ecole Centrale de Lyon. Measurements of wall pressure, far -field acoustic pressure and velocity fluctuations using the hot-wire anemometry were conducted. In addition, advanced post-processing techniques were applied High-accuracy numerical studies focused on selected transitional-flow regimes for NACA-0012 and SD7003 airfoils for which experimental measurements recorded strong flow-acoustic resonant interactions characterized by multiple-tone acoustic spectra. Numerical studies employed a 6th-order Navier-Stokes solver implementing low-pass filtering of poorly resolved high-frequency solution content to retain numerical accuracy.
Distribution Statement:
APPROVED FOR PUBLIC RELEASE