Aeroacoustic integral methods, formulation and efficient numerical implementation

摘要

The paper makes a contribution to the clearer understanding of the physical meaning and domain of applicability of the Flows Williams-Hawkings (FW-H) and Kirchhoff aeroacoustic integral methods. The analytical relationship between the two approaches, and the physical implications involved in the use of the Kirchhoff approach are discussed. In particular, where the Kirchhoff surface cuts into a domain where non-negligible volume sources of Lighthill's Acoustic Analogy are present (domain crossed by a shock, non- uniform flow or vortices for instance), the Kirchhoff integral must be complemented by additional surface integrals to recover the FW-H surface integral.