Influence Of Near Well Fracture Network On Water Drive Law Of Fractured Horizontal Well In Ultra-low Permeability Reservoir

Ultra-low permeability reservoir of large-scale commercial exploitation,thanks to large-scale hydraulic fracturing,to increase productivity,often using waterflooding complement formation energy,hydraulic fracturing of the formation of a complex fracture network and whether water formed on the effective displacement production of low permeability oil fields can play a decisive role.This paper is based on field microseismic testing and hydraulic fracturing data,the relationship between the length of the joints,the height of the joints,and the width of the joints are analyzed,we get the expression between the seam length and the effective ground fluid.At the same time,the general direction of fracture development is determined by using ground stress.We can describe the general form of artificial fracturing cracks,forming suitable for ultra-low permeability reservoir fracturing horizontal wells of the seam network method.For natural fractures and artificial cracks,the evaluation of different numerical simulation methods to adapt to the method.If the number of simulated regions is large and the computational complexity is large,the equivalent permeability can be used to simulate the artificial cracks.If the number of meshes is moderate,the precision of the simulation is relatively high,and the double-Method to simulate artificial cracks.At the same time,the seam of natural fracture and artificial fracture is studied,and the influence of different seam network coupling direction,different seam network structure and different seam size on water injection development are analyzed.The Barton-Bandis permeability model was used to simulate the water injection induced seam during the development of water injection.At the same time,the effects of natural potential closed dynamic fractures and supercracking pressure dynamic fractures on waterflooding were analyzed.It can be seen that the diversion ability of fractures,the length of cracks and the pressure of water injection have a great influence on the development effect.