Position details

Large Eddy Simulation of multiscale systems
Training › Computational Fluid Dynamics - Combustion

Required Education / Niveau requis

Master or Engineering school

From / Date de début

February/April 2013

Duration / Durée

6 months

Context / Contexte

Large Eddy Simulation (LES) of turbulent flows is a growing technique, as it leads to a significant increase of accuracy and predictibility, and allows to run very large size computations on the more and more powerfull super-computers. Its recent application to turbulent combustion has allowed important progress in the field of propulsion and gas turbines.  In such  small systems, the range of flow scales stays suffiiciently limited to allow a good resolution of the flow with LES.  However in larger systems, such as industriel furnaces and heaters, a much larger range of scales appears, from the smallest one near the burner where the flame stands, to the largest corresponding to large size convective motion in the chamber volume. For such systems, the direct application of the LES technique is still too costly in terms of CPU time and new algorithms must be developed.

Description / Description

The objective is to develop a methodology to apply LES to a furnace or a large size combustion chamber. The main difficulty is to adapt the LES technique to the multi-scale nature of the turbulent reacting flow. In a first step, this multi-scale nature will be simply reflected on the mesh (using local mesh refinement or multi-grid techniques). Next, the subgrid scale model will be evaluated on such meshes, and possibly modified to improve its behaviour. Work steps will be the following :

- Bibliography study on multi-scale simulation

- Code learning (AVBP) and simulation set-up

- Simulation on various meshes, with different levels of  refinement, and analysis

- Set-up and run of a multi-grid simulation, using 2 levels, based on coupled computations (one on the fine grid/restricted domain,  one on the coarse grid/full domain, coupled via OpenPalm, coupling software developed at CERFACS)

- Analysis of the behaviour of the subgrid scale model.

Contacts / Contacts

Name: Riber Eleonore
Phone: 05 61 19 31 15
Fax: 05 61 19 30 00
Email: riber@cerfacs.fr

Name: Cuenot Bénédicte
Phone: 05 61 19 30 44
Fax: 05 61 19 30 00
Email: cuenot@cerfacs.fr

Salary / Rémunération

580 Euros/month