Deplacement miscible avec contrastes de densite et de viscosite en milieu poreux. Identification des parametres de deplacement et stabilite en regime de dispersion mecanique

Abstract

The behaviour and estimation of pollutant transport with water in an aquifer are based on the determination of displacement parameters (velocity field, dispersion tensor, kinematic porosity, etc.). We consider the one-dimensional and isothermal displacement of two miscible fluids through an isotropic and homogeneous porous medium in mechanical dispersion. An in situ measurement technique coupled with an impulse response method is used to verify the theoretical solution in the error function (trace case). With viscosity and density gradients, experimental and numerical (application of instability criterion) results are in good agreement. For a quasi-stable displacement, we have shown an asymptotic dispersion regime. The localization of a pollutant front in the studied configuration, is discussed.