par D'Hernoncourt, Jessica ;Kalliadasis, Serafim;De Wit, Anne
Référence The Journal of Chemical Physics, 123, 23, page (1-9), 234503
Publication Publié, 2005
Article révisé par les pairs
Résumé : We consider the influence of heat losses through the walls of a Hele-Shaw cell on the linear stability and nonlinear dynamics of exothermic chemical fronts whose solutal and thermal contributions to density changes have the same signs. Our analysis is based on the reaction-diffusion-convection equations obtained from the Darcy-Boussinesq approximation. The parameters governing the equations are the Damköhler number, a kinetic parameter d, the Lewis number Le, the thermal-expansion coefficient γT, and a heat-transfer coefficient α which measures heat losses through the walls. We show that for thermally insulating walls, the temperature profile is a front that follows the concentration profile, while in the presence of heat losses, the temperature profile becomes a pulse that leads to a nonmonotonic density profile which in turn may lead to a destabilization of an otherwise stable front. © 2005 American Institute of Physics.