稠油出砂侵蚀模型的建立

Development and Solution of Sand Inflow Erosion Model for Cold Heavy Oil Production

考虑流体流动对出砂的影响,以连续方程和达西方程为基础,建立了稠油出砂冷采侵蚀模型,并在一维单相不可压缩条件下进行求解。结果表明,连续出砂会大大提高近井地带的孔隙度,从而改善油藏流动特性,提高稠油产量;而产砂量则出现先大幅度增加而后降低并趋于稳定的特征,这与现场实际资料相吻合,证明了该模型的可靠性。此外,一维模型可以用来指导出砂冷采实验,并进行验证。该模型具有很强的发展前景,可以推广到在径向流、两相流以及考虑岩石骨架塑性变形(流固耦合)等情况下的稠油出砂侵蚀模型的研究中。

The developed sand inflow erosion model for cold heavy oil production is based on the mass conservation law and Darcy's law, considering the effect of fluid flowing on sand inflow/production, and the solution in uncompressible condition of single phase is obtained. The result shows that continuous sand inflow greatly improves the porosity near the well and the performance of fluid flowing, thus increasing the heavy oil production with tendency of sand inflow increasing drastically in the early period, then declining, and finally reaching stability. Such a feature is accordant with the field data. It is demonstrated that the valid model of one dimension can be applied to guide the experiment of sand inflow and cold production, and make validation as well. Hence this model is of bright future for application to the sand inflow erosion model's study under radial flow, two-phase flow, and coupling with rock matrix plastic deformation.