基于一维岩心实验参数的三维油藏采收率预测方法及应用

为进一步提高岩心实验参数利用率、丰富油藏采收率的预测方法、提高预测精度,综合运用各类岩心水驱油实验法、数值模拟方法和油藏工程方法的优点,以一维室内油层物理实验参数为基础,考虑水驱油过程中启动压力梯度对驱油效果的影响,建立了一维水驱油数学模型;同时以各小层产液速度为权系数,将一维数学模型转化为二维剖面模型;在此基础上,利用不同井网下的水驱油波及系数,将二维剖面模型再次转化为三维油藏采收率预测模型,建立了基于一维岩心实验参数的三维油藏采收率预测方法。莫005井区三工河组应用实践表明,该方法预测采收率25.6%与实际标定采收率25%相吻合。由此可见该方法能够通过综合运用各类岩心实验结果,并考虑层间非均质性和井网形式对采收率的影响,避免了实验方法预测和油藏工程方法预测的单一性和不确定性,为油藏采收率预测提供了新的方向和思路。

A three-dimensional oil recovery prediction method based on one-dimensional core experimental parameters

In order to further improve the utilization of the core experimental parameters, to enrich oil recovery prediction methods and to further improve the prediction precision, a one-dimensional mathematical model of water flooding was established by utilizing the advantage of various types of core experimental methods, numerical simulation and reservoir engineering approach. The model is based on the one-dimensional reservoir physics experiment parameters, considering effect of the threshold pressure during water flooding.Moreover, using liquid production rate as weight coefficient, the one-dimensional mathematical model is transformed into a two-dimensional cross-sectional model; on this basis, using water flooding sweep coefficient under different well patterns, the two-dimensional cross-sectional model can be transformed into a three-dimensional model to predict oil recovery. The results in Mo005 well block showed that: the predicted recovery using this method is 25.6%, consistent with 25% of the actual standardized recovery. The method can fully use various types of core results, consider interlayer heterogeneity and well pattern, avoiding the singularity and uncertainties by using simple experimental methods or reservoir engineering methods to predict oil recovery. The method can further enrich oil recovery prediction methods and improve prediction precision, at the same time, it provides a new direction and idea for other researchers.