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Mini-séminaire du LHEEA 14/12/2017: "Simulation of a fixed cylinder in waves using the SWENSE method within a weakly-compressible solver (WCCH)", Maïté Gouin

Le Laboratoire de recherche en Hydrodynamique, Énergétique et Environnement Atmosphérique de Centrale Nantes (LHEEA) organise des mini-séminaires tous les jeudis midi. Rendez-vous en salle de télé-enseignement au bâtiment D les jeudis à 13h45. Allez-y, c'est ouvert à tous !

Le 14 décembre 2017 de 13:45 à 14:30

Le 14 décembre 2017 de 13:45 à 14:30

Le 14 décembre 2017 de 13:45 à 14:30

Le 14 décembre 2017 de 13:45 à 14:30

Cette semaine :

Maïté GOUIN (post-doc H2I)
présentera son travail ayant pour titre "Simulation of a fixed cylinder in waves using the SWENSE method within a weakly-compressible solver (WCCH)" at 1:45 PM.
Résumé : 
"Naval or ocean engineering hydrodynamic problems are usually solved using either potential flow assumption or the full Navier-Stokes equations.  Potential flow solvers provide very fast and accurate results for propagating gravity waves,  but cannot describe the interaction of these waves with structures when viscosity/turbulence play a significant role. On the contrary, Computational Fluid Dynamics (CFD) solvers can accurately predict fluid/structure interactions but are not fully adapted to wave propagation cases because of their inherent numerical diffusion.

The purpose of this work is to combine the advantages of potential flow and CFD solutions through the use of a hybrid SWENSE (Spectral Wave Explicit Navier-Stokes Equations) method. The essence of this method is to pre-calculate the incident flow (waves and/or currents) through a potential flow solver and to insert it within the Navier-Stokes equations to get the SWENSE equations. As a result, only the disturbed flow solution is computed.

In the present work we propose to extend the SWENSE method to an in-house Finite Volume Navier-Stokes solver based on a weakly-compressible approach (WCCH). It is still under development and is already able to model viscous and turbulent flows including complex moving geometries. A fully explicit temporal scheme combined with the weakly-compressible approach is used and a purely Cartesian grid is adopted for numerical accuracy and algorithmic simplicity purposes.  An Adaptive Mesh Refinement (AMR) method embedded within a massively parallel framework is implemented and geometries are automatically immersed within the Cartesian grid.

In the present context, the SWENSE method  needs to be adapted to a weakly-compressible formulation of the Navier-Stokes equations whereas it was only derived under the incompressible assumption in previous works. The final objective will be to impose the incident flow as a highly accurate wave solution (Rienecker & Fenton, HOS). External libraries have thus been built to be used easily in any CFD solver and some interesting test cases have been performed."
Publié le 11 décembre 2017 Mis à jour le 8 juillet 2018