聚合物溶液在油藏孔隙中的流动及微观驱油机理

研究了粘弹性聚合物溶液在盲端孔隙模型中的流动与驱替特性。微观流动实验和数值计算结果均表明，随着事物溶液粘性弹增强（Weissenberg数增大），在孔隙盲端及喉道中的粘弹性涡流加剧，涡流区域也随之扩大；计算得到的粘弹涡特征与Cochrane等给出的实验结果在定性规律上是一致性。这种粘弹涡可将孔隙盲端和喉道中的部位科油分散成油滴或油丝并携带至主流区，使之成为可驱动原油。所以，这种粘弹涡流效应是聚合物溶液提高微观驱油效率的重要机理之一。

Viscoelastic flow and microscopic displacement mechanism of polymer solution in reservoir pores

The flow and displacement characteristics of the viscoelastic polymer solution in the pore model with blind ends are studied. Both microscopic flow experiments and numerical calculation results show that the strength and depth of viscoelastic eddy in the blind ends and throats increase with the increase of Weissenberg number, and this is qualitatively consistent with the experiment results given by Cochrane et al. The part of remaining oil in the blind ends and throats can be dispersed into oil droplets and transported to the main stream by the viscoelastic eddy. It is quite evident that the viscoelastic eddy effect should be the mechanism of increasing microscopic displacement efficiency in polymer flooding.