论文部分内容阅读
水力压裂是低渗油气藏的主要开发手段,传统数值模型所得到的基质-裂缝窜流量以及断裂参数精度不足.为此以流固耦合理论与断裂力学相结合的压裂模型为基础,模拟了水力裂缝扩展过程.在模型中分别引入离散裂缝模型和广义J积分计算基质-裂缝流量交换和断裂参数,并采用动态网格技术对裂缝尖端进行局部加密,以提高模拟的效率和精度.模型计算结果显示,影响水力压裂过程的主要参数中:基质渗透率和压裂液粘度主要影响水力裂缝的最终形态;岩石弹性模量影响裂缝宽度.对压裂车而言,最高工作压力一般都能够满足压裂增产需求,其最大输出功率和最大输出流量是限制压裂能力的主要因素.
Hydraulic fracturing is the main means of development for low permeability reservoirs, and the matrix-fracture flow rate and the accuracy of fracture parameters obtained by traditional numerical models are not enough. Therefore, based on the fracturing model combining fluid-solid coupling theory and fracture mechanics, The hydraulic crack propagation process is introduced.The discrete fracture model and generalized J-integral are respectively introduced into the model to calculate the matrix-fracture flow exchange and fracture parameters, and the dynamic mesh technique is used to locally crack the crack tip to improve the simulation efficiency and accuracy. The calculation results show that among the main parameters affecting the hydraulic fracturing process, the matrix permeability and fracturing fluid viscosity mainly affect the final shape of the hydraulic fractures and the rock elastic modulus affects the fracture width. For fracturing vehicles, the maximum working pressure is generally Which can meet the demand of fracturing stimulation. The maximum output power and maximum output flow are the main factors to limit the fracturing capacity.