This work introduces 3D lattice modeling of hydraulic fracturing initiation and near-wellbore propagation for different perforation models, including spiral perforation, oriented perforation and Tristim perforation. For each perforation model, a total of six perforation tunnels are explicitly modeled and the representative intermediate states are chosen to analyze the results. The numerical simulation results show that the perforation tunnels guide the generation of initial microcracks at the roots of the perforation tunnels once the injection starts, however, the subsequent fracture propagation is controlled by the relative locations of perforation tunnels and the stress interference among different perforation tunnels. The spiral perforation gives the highest breakdown pressure while the Tristim perforation gives the lowest. Trans-wellbore fracture surfaces caused by the generation of large amount of microannulus cracks is the main reason of the pressure breakdown. The magnitude of the breakdown pressure is associated with the level of fracture complexity generated before the breakdown. Despite the variation of breakdown pressure for different perforation models, both the initial minimum pressure after the breakdown and the propagation pressure are nearly identical. The study provides a theoretical basis for understanding fracture initiation and near-wellbore tortuosity.

这项工作介绍了针对不同射孔模型（包括螺旋射孔，定向射孔和Tristim射孔）的水力压裂启动和近井扩展的3D网格建模。对于每个射孔模型，总共将对六个射孔隧道进行显式建模，并选择代表性的中间状态来分析结果。数值模拟结果表明，射孔通道引导了射孔通道根部初始微裂纹的产生，但是，随后的裂缝扩展受射孔通道的相对位置和不同射孔通道之间的应力干扰的控制。 。螺旋穿孔的破裂压力最高，而Tristim穿孔的破裂压力最低。大量微环隙裂缝的产生所引起的跨井眼裂缝面是压力破坏的主要原因。击穿压力的大小与击穿之前产生的断裂复杂程度有关。尽管不同射孔模型的破裂压力有所不同，但破裂后的初始最小压力和传播压力几乎相同。该研究为理解骨折的起爆和近井眼曲折提供了理论基础。尽管不同射孔模型的破裂压力有所不同，但破裂后的初始最小压力和传播压力几乎相同。该研究为理解骨折的起爆和近井眼曲折提供了理论基础。尽管不同射孔模型的破裂压力有所不同，但破裂后的初始最小压力和传播压力几乎相同。该研究为理解骨折的起爆和近井眼曲折提供了理论基础。