Study On Adaptability Evaluation Of Horizontal Well Perforation Mode

As a completion process before hydraulic fracturing,hole injection has a decisive role in the initiation and expansion of hydraulic fractures in the near wellbore.Different hole injection methods form different fracture patterns at the near wellbore end after fracturing under different wellbore conditions,and for horizontal well volume pressure,multiple clusters of fractures under multi-stage and multi-cluster injection determine the communication ability between the horizontal wellbore and the formation,so according to different wellbore conditions,determining the appropriate hole injection methods to improve Therefore,it is important to determine the appropriate injection method to improve the fracturing effect according to different wellbore conditions for efficient development of unconventional reservoirs.In this paper,the true triaxial hydraulic fracturing experimental system is used to design the fracture propagation experiments under different perforation modes,and obtain the fracture propagation patterns under different fault conditions under different perforation modes.On this basis,rock mechanics,elastoplastic mechanics,Damage mechanics and seepage mechanics are combined,and based on the damage evolution criterion of Cohesive unit,Using tube units and connector units to automatically allocate the fracturing fluid injected into each hole or cluster of fractures,establish an integrated hydraulic fracture initiation and propagation model for near wellbore perforation fracturing in horizontal wells.According to the analysis of calculation results,no matter what kind of crustal stress,the fracture shape produced by 180° directional perforation in horizontal wells is superior to other perforation methods,while 60° spiral perforation is more suitable for vertical wells.The relationship between fracture expansion and reservoir is analyzed in different reservoirs,and the relationship between fracture expansion and the number of holes and clusters in dense rock,conglomerate,and carbonate is analyzed in a two-dimensional numerical model under different reservoir conditions,and recommendations are given based on this: under dense rock conditions,a single section with 3 or 5 clusters is used,and the number of single cluster shot holes In conglomerate,single-section 5-7 clusters are used,with less than 8 holes per cluster;in carbonate,single-section 5 or 7 clusters are used,with no more than 10 holes per cluster;meanwhile,a numerical model of single-section multi-cluster shale is established,and the best shot-hole placement scheme for shale is given according to the laminar extension.Based on the adaptability analysis of the shot hole arrangement under different conditions,the matching shot hole arrangement and location are given,which can provide technical support for the construction design of oil and gas fracturing and extraction under different conditions and improve the means of fracturing transformation.