Skip to Main content Skip to Navigation
Theses

Modélisation de paroi et traitement aux interfaces des maillages non-conformes pour les simulations aéroacoustiques avec une approche numérique d'ordre élevé

Abstract : This thesis is devoted to the development of numerical methods to predict jet noise using Large-Eddy Simulation (LES). The LES approach used in this work relies on high-order low-dissipation and low-dispersion implicit finite-volume schemes for spatial discretization. It allows the direct calculation of acoustic sources in turbulent flows and the propagation of sound waves with accuracy. Two numerical methods are developed in order to facilitate the LES computations. The first method focuses on using wall modeling in the near-wall regions instead of resolving the boundary layers. An analytical wall model is combined with the high-order schemes for spatial discretization. A specific spatial discretization, based on a ghost cell reconstruction, is proposed near the walls. Its performance is assessed by performing the LES of a turbulent channel flow at a Mach number of 0.2 and a friction Reynolds number of 2,000, and the LES of an isothermal subsonic round jet at a Mach number of 0.6 and a Reynolds number based on the jet diameter of 570,000. The aerodynamic and the acoustic properties of the flows are in agreement with the direct numerical simulation data and the experimental results of the literature. The second method deals with the development of a treatment at the non-conforming grid interfaces. Non-conforming grids involve discontinuous block interfaces, allowing the use of simplified meshes for the computations. The proposed treatment ensures the compatibility between the spatial discretization schemes and non-conforming meshes. Particular attention is paid to meet the accuracy requirements imposed in computational aeroacoustics. This treatment relies on meshless interpolations. Its validity is evaluated by simulating a vortex convection and a mixing layer development in two dimensions. The results show that the treatment does not produce significant spurious numerical waves nor disturb the flow development near the grid interfaces.
Document type :
Theses
Complete list of metadatas

Cited literature [131 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02375579
Contributor : Abes Star :  Contact
Submitted on : Friday, November 22, 2019 - 9:48:36 AM
Last modification on : Tuesday, October 13, 2020 - 3:27:30 AM

File

TH_T2520_slebras.pdf
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02375579, version 1

Citation

Sophie Le Bras. Modélisation de paroi et traitement aux interfaces des maillages non-conformes pour les simulations aéroacoustiques avec une approche numérique d'ordre élevé. Autre. Université de Lyon, 2016. Français. ⟨NNT : 2016LYSEC008⟩. ⟨tel-02375579⟩

Share

Metrics

Record views

205

Files downloads

73