Source decomposition and reduced-order modeling of an installed F404-GE-103 engine using the optimized-location virtual reference method

Principal component analysis-related methods (i.e., proper orthogonal decomposition or partial field decomposition) are used widely in aeroacoustic applications for source characterization and reduced-order modeling. A previous paper [A. T. Wall et al., J. Acoust. Soc. Am. 144, 1356 (2018)] developed a coherence-based, virtual-reference method for performing physically meaningful PFD known as the optimized-location virtual references (OLVR) method. This paper performs a source decomposition using the OLVR method on acoustical holography data from an installed GE F404 engine. The OLVR-derived partial fields are compared with far-field radiation characteristics and partial equivalent sources are fitted to analytical wavepackets. Characteristics of this reduced-order model are discussed as a function of frequency and engine condition. [Work supported ONR Grant No. N00014-21-1-2069.]