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From 2 November 2021 to 4 November 2021

Fundamentals to understand and analyse high fidelity compressible LES

Jean-François BOUSSUGE |  

Deadline for registration: 15 days before the starting date of each training
Duration : 3 days / (21 hours)

Before signing up, you may wish to report us any particular constraints  (schedules, health, unavailability…) 

at the following e-mail address : training@cerfacs.fr

Satisfaction index

In November 2019, 50% of participants were satisfied or very satisfied

(results collected from 6 respondents out of 12 participants, a response rate of 50%)


This training course enables the participants to reinforce their theoretical knowledge in order to understand and analyze high fidelity compressible Large Eddy Simulation (LES). Numerical methods, boundary conditions, signal processing and unsteady turbulence modeling are the main subjects tackled. Hands-on sessions are organized to put the theoretical courses into practice.

Objective of the training

The objective of this training course is to become familiar with the LES in order to realize and analyze LES of turbulent flows.

Learning outcomes

On completion of this course, you will be able to:

  • Explain the concept of turbulent scale separation
  • Derived LES equations,
  • Choose a subgrid scale model
  • Define a-priori parameters for a LES (mesh, CPU cost…)
  • Become familiar with compressible boundary conditions
  • Analyze a turbulent flow

Teaching methods

The training is an alternation of theoretical presentations and practical work. A multiple choice question allows the final evaluation. The training room is equiped with computers, the work can be done in sub-groups of two people.

Target participants

This training session is for students, engineers, physicists and computer scientists who wish to reinforce or extend their theoretical background to the precise use and analysis of CFD simulations.

Prerequisites and registration

In order to follow this course, you need to:

  • Know Unix commands
  • Have basic knowledge of Python.
  • Know numerical flow simulations.
  • Have level B2 of CEFR (training can take place in French or English depending on the audience).

To verify that the prerequisites are satisfied, the following questionnaires must be completed. You need to get at least 75% of correct answers in order to be authorized to follow this training session. If you don’t succeed it, your subscription will not be validated. You only have two chances to complete them.

Questionnaire 1 : Unix commands

Questionnaire 2 : Python edition

Questionnaire 3 : Numerical flow simulations


After completing the pre-requisite tests and obtaining at least 75% correct answers, you can register:



Referent teacher: Guillaume Daviller



  • Trainees/PhDs/PostDocs : 210 € excl. tax
  • CERFACS shareholders/CNRS/INRIA : 600 €excl. tax
  • Public : 1200 € excl. tax


(Every day from 9h to 17h30)

Jour 1

  • Turbulence and scale separation
    Large Eddy Simulation

Jour 2

  • Subgrid scale models ; discretisation and meshing techniques
    Hybrid simulations RANS/LES ; wall modeling and turbulence injection

Jour 3

  • Acoustics – compressible boundary conditions
    Signal treatment : frequential analysis, spatio-temporal correlations

Evaluation of learning

A final exam will be conducted during the training.


NextSim General Assembly and TC meeting

CERFACS |  16 September 2021

The General Assembly and TC Meeting took place on 15-16 September 2021. CERFACS is involved in the NextSim project (). The primary objective is to increase the capabilities of Computational Fluid Dynamics tools on extreme-scale parallel computing platforms for aeronautical design. This project has received funding from the European High-Performance Computing Joint Undertaking (JU) under grant agreement N° 956104. The JU receives support from the European Union’s Horizon 2020 research and innovation programme and Spain, France, Germany. This project has received funding from the Agence Nationale de la Recherche (ANR) under grant agreement N° ANR-20-EHPC-0002-02. For more information, please visit Read more

Sophie Valcke from Cerfacs co-authored a new book on atmosphere-ocean modelling

CERFACS |  18 August 2021

new book "Atmosphere-Ocean Modelling - Couling and Couplers” by Prof. Carlos R Mechoso, Prof. Soon-Il An and Dr Sophie Valcke has just been published by World Scientific. The present book fills a void in the current literature by presenting a basic and yet rigorous treatment of how the models of the atmosphere and the ocean are put together into a coupled system. Details are available at  Abstract: Coupled atmosphere-ocean models are at the core of numerical climate models. There is an extraordinarily broad class of coupled atmosphere-ocean models ranging from sets of equations that can be solved analytically to highly detailed representations of Nature requiring the most advanced computers for execution. The models are applied to subjects including the conceptual understanding of Earth’s climate, predictions that support human activities in a variable climate, and projections aimed to prepare society for climate change. The present book fills a void in the current literature by presenting a basic and yet rigorous treatment of how the models of the atmosphere and the ocean are put together into a coupled system. The text of the book is divided into chapters organized according to complexity of the components that are coupled. Two full chapters are dedicated to current efforts on the development of generalist couplers and coupling methodologies all over the worldRead more