The increasing use of hydrogen (H2) in industry and transport poses problems in 
terms of the safety of industrial installations. Indeed, H2 is a volatile and 
flammable molecule which can cause destructive explosions. Computational fluid 
dynamics (CFD) constitutes an important tool for designing systems and is a 
complement to experiments, which are expensive and difficult to implement. CFD 
simulations must nevertheless achieve a high level of fidelity. In the case of 
the combustion of H2, the numerical models must in particular take into account 
the effects of thermo-diffusive instabilities, which are a consequence of the 
very high diffusivity of hydrogen, and which generate a significant acceleration 
of the flames. These effects are, however, rarely taken into account in CFD 
models, and are often based on laminar flames, while the interactions between 
instabilities and turbulence are neglected. The objective of this PhD is to 
develop a large eddy simulation model taking into account the effects of thermo-
diffusive instabilities, as well as their interactions with turbulence. The 
model will be developed in the formalism of the thickened flame model (TFM), 
currently used at IFPEN. The thesis will take place according to the following 
steps: (i) Implementation of direct numerical simulations (DNS), making it 
possible to understand and acquire detailed data on the interactions between 
instabilities and turbulence; (ii) development of a model in a TFM context and 
validation on canonical cases; (iii) test of the model on a practical case of 
industrial explosion.

Academic requirements: University Master degree involving CFD, physics and/or 
numerical modelling

Language requirements: Fluency in French or English, willingness to learn French

Academic supervisor: Dr Olivier COLIN, IFPEN, ORCID : 0000-0002-8947-3490