Cerfacs Enter the world of high performance ...

The 17 January 2019 at 14h00




Thermal cracking is an industrial process sensitive to both temperature and pressure operating conditions. The use of internally ribbed reactors is a passive method to enhance the chemical selectivity of the process, thanks to a significant increase of heat transfer. However, this method also induces an increase in pressure loss, which is damageable to the chemical yield and must be quantified. Because of the complexity of turbulence and chemical kinetics, and as experimental measurements remain very expensive, the real advantage of such geometries in terms of selectivity is however poorly known and hard to assess.

This work aims at evaluating the real benefits of internally ribbed reactors in terms of chemical yields, and at proposing innovative reactor designs. This is made possible via Large Eddy Simulations (LES), which are used to study the reactive flow inside several reactor geometries. The AVBP code, which solves the Navier-Stokes compressible equations for turbulent flows, is used in order to simulate thermal cracking thanks to a specific numerical methodology. In particular, the effect of pressure loss and heat transfer on chemical conversion are compared for both a smooth and a ribbed reactor in order to conclude about the impact of wall roughness in industrial operating conditions. An optimization methodology, based on series of LES, is finally developed and an innovative reactor design for thermal cracking applications, which maximizes the chemical yield, is proposed.


Kevin VAN GEEM              Ghent University                             Referee

Laurent JOLY                       ISAE SUPAERO Toulouse           Referee

Tom ALDERWEIRELDT    TOTAL Ghent                                  Member

Angelo IOLLO                      Université de Bordeaux                 Member

Franck NICOUD                  Université de Montpellier              Member

Marouan NEMRI                 TOTAL Gonfreville                         Invited member

Bénédicte CUENOT           CERFACS Toulouse                      Advisor

Eléonore RIBER                  CERFACS Toulouse                      Co advisor



Thierry Poinsot officially entered the French Academy of Sciences

CERFACS |  8 November 2021

Thierry Poinsot officially entered the French Academy of Sciences on October 12. See presentation here :Read more

The AVBP code from CERFACS at the heart of for PRACE projects from the 23rd call

CERFACS |  30 September 2021

Cerfacs is involved in three PRACE projects of the 23rd call for which hour allocation runs from 01/10/2021 to 30/09/2022. Researchers from ECL/LMFA UMR5509 (Ecole Centrale de Lyon) and IMFT (UMR 5502) laboratories have earned projects entirely based on the use of the LES solver developed by Cerfacs AVBP and involve the support of experts from the CFD and COOP teams underling the importance and effectiveness of collaborations between French labs and Cerfacs. Alexis Giauque from ECL/LMFA UMR5509 (Ecole Centrale de Lyon) has obtained not only one but two PRACE projects! The first project LESFAN (RA0101, 30 000 000 CPU hours on Irene/Rome TGCC) is based on the use of AVBP in the turbomachinery version to study the generation of noise by a fan of a real airplane engine. The second, PRACE-EDGES (RA0101, 40 000 000 CPU hours on Irene/Rome TGCC) focuses on LES modeling of dens gas in complex geometries. To do so, the LMFA Team has developed advanced thermodynamic closures in AVBP allowing the direct simulation of such flows. Laurent Selle from IMFT (UMR 5502) has received CPU hours for the GASTON project (RA0061, 30 000 000 CPU hours on Marenostrum BSC) which aims to study the structure of hydrogen flames in porous materials. For this, IMFT and Cerfacs will perform coupled simulations considering the reactive flow with AVBP as well as the conduction in the porous medium with AVTP which is known to play an central role in the flame stabilization process. Carlos Perez Arroyo from IMFT (UMR 5502) received 16 Mh CPU hours on Joliot-Curie Skylake partition to support his project WONDER.Read more