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The 16 May 2017 at 14h00

PhD Defense: Julien VANHAREN – High-order numerical methods for unsteady flows around complex geometries

Marie LABADENS |  Cerfacs, Salle de conférence Jean-Claude ANDRÉ  |  


This work deals with high-order numerical methods for unsteady flows around complex geometries. In order to cope with the low-order industrial Finite Volume Method, the proposed technique consists in computing on structured and unstructured zones with their associated schemes: this is called a hybrid approach. Structured and unstructured meshes are then coupled by a nonconforming grid interface. The latter is analysed in details with special focus on unsteady flows. It is shown that a dedicated treatment at the interface avoids the reflection of spurious waves. Moreover, this hybrid approach is validated on several academic test cases for both convective and diffusive fluxes. The extension of this hybrid approach to high-order schemes is limited by the efficiency of unstructured high-order schemes in terms of computational time. This is why a new approach is explored: The Spectral Difference Method.

A new framework is especially developed to perform the spectral analysis of Spectral Discontinuous Methods. The Spectral Difference Method seems to be a viable alternative in terms of computational time and number of points per wavelength needed for a given application to capture the flow physics.


Pr. P. CINNELLA                   ENSAM, Paris                   Referee
Pr. R. TURPAULT                 IMB, Bordeaux                   Referee
Pr. P.-H. MAIRE                    CEA/CESTA, Bordeaux     Member
Pr. B. KOOBUS                    IMAG, Montpellier              Member
Dr. M. de la LLAVE PLATA   ONERA, Châtillon              Member
Dr. G. PUIGT                        CERFACS, Toulouse         Advisor
Dr. M. BARTH                      AIRBUS, Toulouse              Industrial Supervisor



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