非均质水驱油藏开发指标预测方法

A new method for prediction of heterogeneous reservoir development index by waterflooding

运用数值模拟法预测非均质油藏开发指标及剩余油饱和度分布的工作量大，耗时长，技术要求高。考虑实际油田井网布置的不规则性及储层的非均质性，基于油藏工程理论，推导并建立了考虑储层非均质性的水驱油藏开发指标预测方法。该方法根据注采井配置关系和渗流阻力，将油田动态劈分为多个注采单元，对各注采单元的渗透率、孔隙度、储层厚度等非均质参数进行等效处理，再将各注采单元转化为均质单元；采用物质平衡原理和Buck-ley—Leverett径向水驱油理论预测各单元开发动态，计算含水率和剩余油饱和度等指标，进而得到整个油藏的开发指标。与传统油藏数值模拟方法相比，新方法占用内存少、速度快、效率高。对断块老油田进行实例验证分析表明，新方法预测单井和全油田10a含水率变化与数值模拟结果的相关系数达0．9934～0．9996，预测10。剩余油饱和度与数值模拟结果吻合。

Considering the actual conditions of irregular well pattern and heterogeneity in reservoir, and based on the reservoir engi-neering theory, a method to predict the residual oil distribution and dynamic development indexes has been proposed herein. The meth-od first splits the oil field into multiple units dynamically and the units can be equivalent to homogeneous one, so that, we can use theBuckley-Leverett waterflooding theory to predict the dynamic development indexes of every unit and then calculate the entire reservoirdevelopment indexes. Compared with the numerical simulation method, the new procedure runs more quickly and requires less comput-er memory. The analysis on the application of theory above in an oil reservoir with 16 wells shows that the results of the method are basi-cally consistent with the numerical simulation method, which is of significant value for field application.