Christophe BUET
Research Engineer in numerical analysis and holder of an HDR in applied mathematics, Christophe Buet develops new models and new numerical methods for the numerical simulation codes. He is interested in kinetic equations for the modelisation of the radiation transfert and the gaz-particle interation. He is currently superving a thesis.
Kinetic and Related Models, 2023
Abstract
The coupling through both drag force and volume fraction (of gas) of a kinetic equation of Vlasov type and a system of Euler or Navier–Stokes type (in which the volume fraction explicity appears) leads to the so-called thick sprays equations. Those equations are used to describe sprays (droplets or dust specks in a surrounding gas) in which the volume fraction of the disperse phase is non negligible. As for other multiphase flows systems, the issues related to the linear stability around homogeneous solutions is important for the applications. We show in this paper that this stability indeed holds for thick sprays equations, under physically reasonable assumptions. The analysis which is performed makes use of Lyapunov functionals for the linearized equations.
Finite Volumes for Complex Applications VII-Elliptic, Parabolic and Hyperbolic Problems, 2014
abstract
Abstract
We are interested in the study of numerical schemes for the homogeneous in space asymptotic limit in the non equilibrium regime of the relativistic transfer equation. This limit leads to a frequency drift term modeling the Doppler effects for photons, and our aim is to design costless well-balanced schemes. One difficulty is that wave speed may vanish, which implies that standard well-balanced schemes constructed by discretizing the source term at the interfaces and by using a Godunov scheme may become inconsistent in this limit. This is indeed observed numerically.