在封闭地层中非牛顿幂律流体压降特征分析

Pressure drawdown analysis for the non-newtonian power-law fluid in bounded reservoirs

研究非牛顿流体压降特征有助于提高聚合物驱油或常规稠油开采效果。本文首先用Laplace变换方法给出了封闭地层中非牛顿幂律流体不稳定渗流数学模型的解析解式,然后通过渐近分析给出了比较完整的压降流动期表现公式,其中晚期拟稳态表达式是一个新的结果,而通过流动期渐近公式可以对非牛顿幂律流体压降测试数据进行简洁分析,文中给出了具体应用方法和步骤。

It is functional to improve either polymer flooding or custom heavy oil recovery that to identify pressure drawdown characteristics of non-Newtonian fluids. Firstly the paper presents an analytical solution to the mathematical model describing the non-Newtonian power-law fluid flow in a circular bounded reservoir by Laplace transformations. Secondly asymptotic formulas are obtained to express the flow regimes during the pressure drawdown process. Especially, in the formulas there is a new expression to depict the last pseudo-steady state ofnon-Newtonian power-law fluid transient flow in the bounded reservoir. The formulas can be used to make a concise interpretation for the well-test data while two practically applied procedures about them are shown in detail in the paper.