Large Eddy Simulation Subgrid Scale Models and Applications with Code_Saturne on Different Types of Meshes

Thomas Norddine
Seminar

First and second order subgrid scale (SGS) based Large Eddy Simulation turbulent models are very convenient to design hybrid RANS-LES models and perform Lagrangian particles tracking. Besides the additional subgrid scales datas yielded by those models, they rely on softer hypothesis and should present a larger validity domain than the ones based on pure eddy viscosity formulations. However, they require solving of additional equations for SGS quantities.

In this work, we present first and second order models implemented in the open source colocated finite volume code Code_Saturne, developed by Électricité de France. They have been tested on existing or specifically designed validation cases and compared to experimental data or DNS results. As a first validation step, a new Decaying Isotropic Turbulence case adapted to these new models has been developed to work on both hexahedral and tetrahedral meshes. Then models near-wall behavior has been investigated with a plane channel flow. Finally, two test-cases involving complex physics have been designed and run for further validation : a flow through a 40 ̊bended pipe in which Dean vortices are tackled and a buoyancy aided flow in a periodic circular pipe where the laminarization phenomenon is clearly observed.