Considerations for array design and inverse methods for source modeling of full-scale jets

Microphone array-based measurements of full-scale jet noise sources necessitate the adaptation and incorporation of advanced array processing methodologies. Arrays for full-scale jets measurements can require large apertures, high spatial sampling densities, and strategies to account for partially coherent fields. Many approaches have been taken to sufficiently capture radiated noise in past jet noise investigations, including patch-and-scan measurements with a small dense array, one-dimensional measurements along the extent of the jet in conjunction with an axisymmetric assumption, and full two-dimensional source coverage with a large microphone set. Various measurement types are discussed in context of physical jet noise field properties, such as spatial coherence, source stationary, and frequency content.