泡沫驱等效数学模型建立及机制分析

Establishment and Mechanism Analysis on an Equivalent Mathematical Model for Foam Flooding

随着泡沫剂在采油中的广泛应用,出现了许多泡沫驱的数值模拟方法。本文着重研究了泡沫的聚并机制和驱油机制,在此基础上建立了一种泡沫驱的等效数学模型,运用IMPES法对模型进行求解,并计算阻力因子值调整注入量,模拟泡沫的调剖效果,同时通过典型算例验证了该等效模型的可行性。对比了水驱、泡沫驱岩心中压力分布、饱和度分布及驱油效率,结果表明,泡沫对高渗透率层起到了很好的封堵作用,使采收率得到一定程度的提高。

With foam is widely used in the oil extraction, various methods involving the numerical simulation of foam flow in porousmedia are appeared. Therefore, the research on the characteristics and mechanism of the foam in the oilfield is definitely necessary. Based on the physical properties of foam, coalescence mechanism and oil displacement mechanism of foam flooding, an equivalent mathematical model of the technology is developed. The parameters for the model are corrected by the value of the resistance factor. The solution of the mathematical model is obtained by using IMPES method. Through the typical example, the equivalent mathematical model is proven to be feasible. The calculation conditions for the typical example are given. Double tube core flooding is simulated, and then the displacement effects between foam flooding and non-foam flooding are compared with each other. The core pressures of water flooding and foam flooding, saturation distributions as well as flooding efficiency are compared, the model is proven. The results show that the foam possesses a good plugging capacity to the layer with high permeability and the oil recovery could be efficiently enhanced by the foam flooding.