BYU

Abstract by Jacob A. Ward

Personal Infomation


Presenter's Name

Jacob A. Ward

Degree Level

Undergraduate

Co-Authors

Kevin M. Leete
Kent L. Gee
David F. Van Komen
Tracianne B. Nielsen
Alan T. Wall
J. Micah Downing
Michael M. James

Abstract Infomation


Department

Physics and Astronomy

Faculty Advisor

Kent Gee

Title

Comparing two inverse array methods for sound field reconstructions of noise radiated from a high-performance jet aircraft

Abstract

Because direct flow measurements of tactical aircraft jet engines are not currently possible, acoustic source characteristics are instead inferred from array processing methods. Models obtained through these methods are then used to reconstruct the surrounding sound field. This paper compares two such methods using the same array data from a high-performance military aircraft.  Hybrid beamforming (HBF) and multisource statistically-optimized near-field acoustical holography (M-SONAH) have both been used previously for jet noise sound field reconstruction but are compared here for the same input data.    A 71-element linear array of equally spaced microphones was placed approximately parallel to the shear layer covering 32 meters.  Complex pressures obtained from this array served as the input to both methods.  Comparing the methods’ results with measured sound field data showed favorable agreement at mid frequencies with varying results for low and high frequencies.  While the methods continue to have their relative strengths and reasons for use, this favorable agreement indicates that an improved understanding of military jet noise has been achieved.