PhD defense: Robin CAMPET – “SIMULATION AND OPTIMIZATION OF STEAM CRACKING PROCESSES”
Thursday 17 January 2019 at 14h00
Phd Thesis CERFACS, SALLE DE CONFÉRENCE JC ANDRÉ - TOULOUSE
Abstract
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.
Jury
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