Seminar: The Aeroacoustics of Three-Steam Jets

Dr. Brenda Henderson, NASA Glenn Research Center

All dates for this event occur in the past.

N056 Scott Lab
201 W. 19th Ave.
Columbus, OH 43210
United States

Abstract:

An experimental investigation of the noise produced by high-subsonic three-stream jets was conducted.  The nozzle system consisted of externally-mixed-convergent nozzles and an external plug.  Bypass-to-core area ratios between 1 and 1.75 and tertiary-to-core area ratios between 0.4 and 1.0 were included in the study.  Axisymmetric and offset tertiary nozzles were investigated for heated and unheated jet conditions.  For axisymmetric configurations, the addition of the third stream was found to reduce mid- and high-frequency acoustic levels in the peak-jet-noise direction with decreasing bypass-to-core area ratio.  The addition of the third stream also decreased peak acoustic levels in the peak-jet-noise direction for moderate bypass-to-core area ratios.  Offset configurations included s-ducts and third-stream nozzle inserts.  Inserts were found to produce acoustic levels similar to those for the axisymmetric jet for azimuthal observation locations of interest.  Acoustic benefits achieved with s-ducts were not adequately captured with predictive tools possibly due to the inability of the RANS solutions to capture the three-dimensional effects evident in the Particle Image Velocimetry results.

About the Speaker:

Brenda Henderson is a senior researcher in the Acoustics Branch at the National Aeronautics and Space Administration (NASA) Glenn Research Center.  As principal investigator, her research projects have included noise-reduction technology development, sound-source mechanism investigations, and noise- reduction model development for subsonic and supersonic jets.  Previously, Henderson served as team lead for the jet noise group at NASA Langley Research Center in Hampton, Virginia.  She provided direction and leadership for the Langley Jet Noise Laboratory (JNL) by developing laboratory testing procedures, directing a team upgrading the JNL data and control communication systems, upgrading and programming data acquisition systems, interfacing with NASA projects to ensure laboratory funding streams, coordinating externally funded research projects, and serving as principal investigator for jet noise research at Langley.  She has written over 30 papers on fluid mechanics and aeroacoustics. 

Henderson received a B.S degree in Engineering from Colorado School of Mines and M.S. and Ph.D.  degrees in Mechanical Engineering from University of Houston.

Hosted by Professor Mike Benzakein