Fluid Seepage Characteristics and Influence Mechanism in Propped Fractures by Hydraulic Fracturing
To understand the fluid seepage characteristics of propped fractures and their influ-ence mechanisms,this paper constructs a numerical model of single-phase fluid flow in the pore structure of propped fractures and a three-dimensional model of propped fractures based on the physical experiments on the conductivity of proppant-filled fractures.The seepage mechanism of fluid in propped fractures was revealed by studying the fluid seepage distribution and the spatial distribution of the pore structure of porous media.The results showed that the fluid seepage in the propped fracture space was distributed unevenly,"open channels"with high conductivity gradually emerged from the bottom to the top of the fracture,and the flow velocity increased une-venly.The porosity gradually increased from the bottom to the top layer in the supported frac-ture,the volume porosity decreased first and then increased,the force chain distribution also in-creased first and then decreased,and volume porosity was formed by the stacking of surface po-rosity through the"force chain"mechanism.The porosity distribution in the propped fractures was inconsistent with the conductivity distribution.The horizontal surface porosity directly af-fected the seepage speed.The larger the surface porosity,the faster the flow velocity.
proppanthydraulic fracturingfractureconductivityporous media
万方数据
维普
