地层渗透参数反演计算

利用渗流源网格压力(及井底压力)对网格渗透率导数关系(称为渗透率压力场敏感系数)实现由三维渗流方程压强数值解计算井底压力对网格渗透参数导数的计算.基于渗透率压力场敏感系数的计算结果构造地层渗透参数反演方程,由多井系统井压监测数据实现反演地层渗透参数的计算.算例显示:反演方法对均匀(或分块均匀)油藏模型的计算取得了较好的结果,反演迭代10次后计算结果与模型参数的最大相对误差收敛于1%之内.该方法对油藏动态模拟研究及实现油藏参数动态跟踪具有实际意义.

Numerical Inversion for Permeability Parameters of Formation

With relation of well-bore and grid-block pressure with any grid permeability parameters of formation (sensitivity coefficients of permeability field), we derived derivatives with respect to permeability for well indices. Numerical derivatives of well-bore pressure with respect to permeability of any grid with numerical solution of 3D fluid equation in porous media are given. Numerical calculation of sensitivity coefficients of permeability field for multi-well system is realized. Based on sensitivity coefficients, an inverse iterative equation is constructed by conjugate method. Numerical calculation for permeability parameters of formation is realized. It shows that:If permeability is uniform or block uniform, relative error of inverse permeability is less than one hundredth as inversely iterating 10 times. It is significant for dynamic simulation and examination of reservoir.