Non-linear interactions of dynamic reactive interfaces in porous media

Viscous fingering of reactive miscible flow displacements in a homogeneous porous media is examined. A general model where the two reactants and the chemical product have different viscosities is adopted. The problem is formulated using the continuity equation, Darcy's law, and volume-averaged forms of convection–diffusion–reaction equations for mass balance, and is solved using a pseudo-spectral method. A parametric study was performed to examine the effect of the Peclet number and the log-mobility ratios between the chemical product and the reactants. It is shown that the development and growth of the instability as well as the efficiency of the reaction expressed in terms of the amount of chemical product can be predicted based on the mobility ratio at the initial front between the two reactants and effective mobility ratios between the chemical product and either one of the two reactants. Furthermore, it is reported that larger Peclet numbers lead to slower rates of chemical production.