On a boundary layer phenomenon in acoustic media

Hélène Barucq 1 Juliette Chabassier 1 Marc Duruflé 1 Victor Péron 2, 3, 1
1 Magique 3D - Advanced 3D Numerical Modeling in Geophysics
LMAP - Laboratoire de Mathématiques et de leurs Applications [Pau], Inria Bordeaux - Sud-Ouest
2 LMAP - Laboratoire de Mathématiques et de leurs Applications [Pau]
3 UPPA - Université de Pau et des Pays de l'Adour
Abstract : In this work we describe a boundary layer phenomenon which occurs inside the atmosphere of the sun. As an application we derive new approximate boundary conditions. The boundary layer phenomenon which occurs in this context has several similarities with the so-called skin effect phenomenon in electromagnetism. We investigate a transmission problem which is modeling the propagation of an acoustic wave inside heterogeneous media and in time-harmonic regime. This problem is set in a domain which represents the sun and its atmosphere. The specific feature of this problem lies in the presence of a small parameter $\delta$ which represents the inverse rate of the exponential decay of the density inside the atmosphere. This problem is well suited for the notion of equivalent conditions and the effect of the atmosphere on the sun is as a first approximation local. First we present a multi-scale expansion in power series of $\delta$ for the solution $u$ of the problem. Then we derive equivalent conditions up to the fourth order of approximation with respect to $\delta$ for the solution $u$. This approach leads to solve only equations set inside the sun. We present numerical results and numerical validations to illustrate the accuracy of the asymptotic models.
Document type :
Conference papers
Complete list of metadatas
https://hal.inria.fr/hal-01691616
Contributor : Victor Péron <>
Submitted on : Wednesday, January 24, 2018 - 12:53:44 PM
Last modification on : Monday, January 13, 2020 - 2:38:06 PM
Long-term archiving on: Thursday, May 24, 2018 - 6:09:59 PM

File

wonapde_13january.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : hal-01691616, version 1

Collections

CNRS | UNIV-PAU | LMA-PAU | INSMI | TDS-MACS | INRIA

Citation

Hélène Barucq, Juliette Chabassier, Marc Duruflé, Victor Péron. On a boundary layer phenomenon in acoustic media. WONAPDE 2016 - 5th Chilean Workshop on Numerical Analysis of Partial Differential Equations, Jan 2016, Concepción, Chile. pp.1-42. ⟨hal-01691616⟩

Export

BibTeX TEI DC DCterms EndNote

Share

Metrics

Record views

104

Files downloads

549

 

 

Contact

archive-ouverte@inria.fr