Impact of multipole matching resolution on supersonic aircraft sonic boom assessment

Abstract

Sonic boom assessment methods through numerical analysis have been ever-evolving since the development of the fundamental theory. With the growing need for e©cient low-boom design tools and the increasing computational resources, original approaches using advanced numerical simulation techniques have been developed. Among the various existing methods, the three-layer resolution introduced in the 1990s is very convenient for low-boom aircraft design. It is based on near-¦eld computational §uid dynamics (CFD) calculation which is matched with the far-¦eld propagation code using a description of the source with multipoles before undergoing classical acoustic propagation through atmosphere. The present paper reviews the theory of the near-to far-¦eld matching as well as the di¨erent resolution approaches and their limits. The impact of the resolution method on the ground propagated signal is also presented.

Multiobjective Design Optimization Using Nash Games

“…The sonic boom at ground is evaluated using the three-layer approach (36). After the near field has been calculated by CFD, the pressure is interpolated on a cylinder around the aircraft.…”

Cooperation and Competition Strategies in Multi-objective Shape Optimization - Application to Low-boom/Low-drag Supersonic Business Jet

“…39 The CFD computation is performed in the near-field and a multipole decomposition for near to far-field matching is performed. 40 The acoustic perturbation is then propagated to the ground through a stratified atmosphere with an acoustic code (e.g non-linear acoustic ray-tracing).…”