Effective conductivity for the fracture-continuum model

[jbrezmorf]

• [ ] Compute intersection of fractures with the mesh triangles.
• [ ] try to replace set fractures of size in (L/100, L/10) by heterogeneous conductivity on a mesh with step ~ L/50 Verify that effective conductivity have same distribution.
• [ ] Try two level model. DFN vs. only small fractures replaced. Again compare effective conductivity distributions.
• [ ] Try different replacement schemes.
• [ ] Three level model. full DFN vs. two level vs. three level: samllest fractures replaced by random corellated conductivity, middle fractures replaced, large disctrete fractures.