“…We give a wellposedness result that does not rely on the imposition of pressure in part of the boundary of the fracture network, thus including a fully immersed fracture network. We present and analyze a mimetic finite difference formulation for the problem, providing convergence results and numerical tests.Article published by EDP Sciences c EDP Sciences, SMAI 2018Even if the use of a geometrically reduced model avoids the need for extremely refined or anisotropic grids inside the fractures, the construction of a computational grid for realistic cases is a challenging task (see, for instance, [22]): a fractured oil reservoir can be cut by several thousands of fractures, often intersecting or very close together. A computational grid conforming to the fractures can thus be characterized by very small elements and low quality, due to high aspect ratios and small angles.…”