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

Personal Author(s):

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.

Subject Categories:

  • Aerodynamics
  • Acoustics
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE