Numerical study of proppants transport and distribution in rock fractures

The proppants' transport, displacement, and distribution in rock fractures were numerically studied. A realistic three-dimensional rock fracture geometry was generated using the Brown method. Lagrangian proppant tracking and the Eulerian approach for fluid flow were used to simulate the proppants laden flow inside the rock fracture. The pressure gradient drives the four-way coupled proppant-laden flow in the streamwise direction. Different horizontal and vertical fracture configurations were considered. Coverage of rock fracture by proppants were reported for various test cases with different proppant sizes and rock fracture apertures. It was shown that the fracture coverage changes dramatically by including a realistic surface roughness compared with a smooth channel fracture model. It was also shown that the particle diameter and the mean aperture significantly affect the fracture coverage, and the optimum proppant size for a given aperture was evaluated. As a result of proppants packing over time, the flow rate in the fracture varies with time. Propagation and placement of proppants into rock fractures from the injection until the steady flow is reached were presented.