کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4546989 | 1627081 | 2011 | 9 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Applicability regimes for macroscopic models of reactive transport in porous media Applicability regimes for macroscopic models of reactive transport in porous media](/preview/png/4546989.png)
We consider transport of a solute that undergoes a nonlinear heterogeneous reaction: after reaching a threshold concentration value, it precipitates on the solid matrix to form a crystalline solid. The relative importance of three key pore-scale transport mechanisms (advection, molecular diffusion, and reaction) is quantified by the Péclet (Pe) and Damköhler (Da) numbers. We use multiple-scale expansions to upscale a pore-scale advection–diffusion equation with reactions entering through a boundary condition on the fluid–solid interface, and to establish sufficient conditions under which macroscopic advection–dispersion-reaction equations provide an accurate description of the pore-scale processes. These conditions are summarized by a phase diagram in the (Pe, Da)-space, parameterized with a scale-separation parameter that is defined as the ratio of characteristic lengths associated with the pore- and macro-scales.
Journal: Journal of Contaminant Hydrology - Volumes 120–121, 1 March 2011, Pages 18–26