利用边界元方法研究非封闭边界均质油气藏井底压力动态特征

BOUNDARY ELEMENT METHOD RESEARCH ON BOTTOMHOLE PRESSURE BEHAVOIR IN NON-CLOSED BOUNDARY OIL AND GAS RESERVOIRS

在实际油藏中非封闭边界普遍存在。对于恒压边界和封闭边界的渗流问题,可以采用常规方法进行求解;但对于非封闭边界的渗流问题,采用常规方法不能得到有效的解决。论述了应用边界元方法(Boundary Element Method) 研究非封闭边界均匀介质油藏中的渗流力学问题,建立并求解考虑井筒储存效应和表皮效应影响的任意形状非封闭边界试井解释数学模型,对渗流微分方程进行拉普拉斯变换,用边界元方法进行处理得到拉普拉斯空间解,再采用 stehfest数值反演算法求得实空间解,并对井底压力动态的曲线特征进行了分析。

Non-closed boundary reservoirs are very widespread in reality. As for the percolation problem of constant pressure boundary and closed boundary, routine method can resolve it. But as for the percolation problem of non-closed boundary, routine method did not work effectively, the Boundary Element Method to study the non-closed boundary mathematical model of well testing interpretation was presented in the paper, which was Laplace transform to the percolation differential equation, the solution in the Laplace space with the Boundary Element Method and then the solution in the real space with the Stehfest Numerical Method was worked out, which can be used to analyze the hole-bottom pressure behavior.