Flow Properties Of Fluid In Fractured Rock

Rock fractures are affected by mining. Its structure influences the fluid flow behavior of fractured rock. We propose a series-parallel equivalent model to describe the fluid flow in single rough rock fracture and define the applicable conditions. By use of this model, the parallel plates theory analysis of rough fracture flow yields the expression of aperture for laminar flow, as a weighted harmonic mean of cubed apertures of local fracture segments with parallel walls.And the excess loss of pressure drop caused by varied aperture in facture generates deviation from the cubic law, as the effect mechanism of roughness on fracture fluid flow, its influence factor and change rule are gotten. Used the excess loss factor of pressure drop, series-parallel model is modified. Based on that, the influence of fractures connection ways on fluid flow in fracture network is investigated. We found the cubic law can give a nice approximation of flow for the main5connection modes, and the series connection and’X’cross connection would come out a slightly larger loss of excess pressure drop. As a further study of fluid flow in fractured rock, a3D model of fracture is build by means of CT images of fracture, and in which flow simulation is carried out to analyse the influence of roughn and contact on flow behavior.