Relation between the Generalized Acoustic Analogy and Lilley's Contributions to Aeroacoustics

Abstract

This paper reviews Lilley's reformulation of Lighthill's equation and shows that it can be obtained as a special case of a much more general acoustic analogy. It also shows how this generalized analogy can be used to eliminate some of the difficulties that arise when more conventional parallel flow analogies are applied to high speed jets. And, finally, some recent applications of these ideas are discussed.