A lightweight hybrid method to estimate the linear acoustic damping of arbitrarily complex geometries

Geoffrey Searby (1) , Aurélie Nicole (2) , Gérard Ordonneau (2) , Mohammed Habiballah (2)

1 IRPHE - Institut de Recherche sur les Phénomènes Hors Equilibre
2 ONERA - The French Aerospace Lab [Châtillon]

We first recall the classical results for the laminar dissipation of acoustic energy in an acoustic boundary layer. We then show how this result can be used in conjunction with a Helmholtz solver to calculate the laminar damping of a chamber of arbitrary geometry. The approach is validated by application to a trivial geometry for which the result is known analytically. We present results for cases of increasing complexity The computational effort is lightweight, ranging from a few seconds of CPU time for a simple axisymmetric geometry, to a few minutes for a 3-D case with low symmetry. These test cases are non reacting, but the approach can be extended to accommodate strong temperature variations, provided the temperature and density fields are known. Finally we discuss the limitations of this approach.

Domaines: Acoustique [physics.class-ph]; Acoustique [physics.class-ph]; Milieux fluides et réactifs

Geoffrey Searby, Aurélie Nicole, Gérard Ordonneau, Mohammed Habiballah. A lightweight hybrid method to estimate the linear acoustic damping of arbitrarily complex geometries. 3rd European Conference for Aerospace Sciences (EUCASS), Jul 2009, Versailles, France. pp.CDROM ISBN 978-2-930389-47-8. ⟨hal-00418831⟩