Study On Formation Mechanism Of Fracture Network After Fracturing In Shale Gas Reservoir

Presently,hydraulic fracturing is a key scientific methodology in oil and gas optimum field development phase to improve shale gas production.In the present research,the stress distribution of reservoir rock in open hole and perforating completion has discussed.After considering the effect of hydrocarbon fluids that force on well wall and fracturing fluid filtration,the distribution model of rock stress field in open hole has established.The effect of stress concentration factor and the stress distribution model of injection well is explained.By using the mathematical model with addition of method of controlling variables,the shear stress,vertical stress,and maximum circumferential stress of the reservoir rock is calculated that explain the theoretical basis for the field fracturing operation.Secondly,four models of crack coupling,discriminant conditions,and occurrence process are described by using mathematical model.The stress state of the crack intersection is analyzed,and the relationship among shear stress,normal stress,and approach angle is calculated.Finally,through ABAQUS finite element numerical simulation software,the influence of different approach angles on the artificial fracture propagation in the reservoir with natural fractures is analyzed.It verifies the previous theoretical results,which has certain guiding significance for the field construction.