Simulation of salinity- and thermohalinedriven flowin fractured porous media

We investigate salinity- and thermohaline-driven flow in a heterogeneous porous medium in which the heterogeneity is due to the presence of fractures. In our study, fractures delimit thin regions of space occupied by a porous medium whose properties are markedly different from those of the porous medium enclosing them.We formulate some benchmark problems in which fractures are present, and solve them by adopting two approaches: (i) The fractures have the same dimension, d, as the enclosing medium and are said to be d dimensional; (ii) the fractures are viewed as (d - 1)- dimensional manifolds, and the equations of density-driven flow are obtained by averaging the d-dimensional laws over the fracture width. We use both approaches as long as salinity-driven problems are considered, and we use the first approach only for the solution of the thermohaline problems. Our aim is twofold: (a) testing the reliability of the (d - 1)-dimensional approach for the considered examples, and (b) studying the effect of fractures on heat transport.