井筒与油藏耦合条件下的水平井非稳态产能预测(Ⅰ)——数学模型

TRANSIENT PERFORMANCE PREDICTION OF HORIZONTAL WELL WITH COUPLED IN WELLBORE AND RESERVOIR PART 1: MATHEMATIC MODEL

如何准确有效地预测水平井产能是进行油藏工程分析和采油工艺设计的重要基础 ,常规的稳态产能预测方法由于内在理论缺陷导致严重的误差。以不稳态渗流理论为基础 ,将水平井的油藏渗流与水平井井筒流动视为一个相互作用的整体 ,建立油藏与井筒耦合条件下的不稳态流动数学模型 ,在井筒流动模型中考虑流体磨阻、动量变化、井筒壁面流入的混合干扰等复杂因素 ,应用边界积分法建立井筒油藏耦合模型 ,可以与不同的油藏模型组合 ,从而为水平井的油藏工程研究、完井及采油工程设计提供更先进的手段。

It is an important base for the analysis to reservoir engineering and the design for the oil production method to how to predict the productivity of the horizontal well accurately. For itself theoretical limitation, there is the serious error on the commonly method to predict the stable productivity. This paper is based on the unsteady flow theory and looks on the reservoir flow and wellbore flow of horizontal well as a coupling system. The transient flow mathematic model under the coupling of the reservoir and wellbore was established. It has considered some complicated factor, such as the fluid friction loss, the change of momentum, the inflow of the sidewall of wellbore etc. The model is based on boundary integral method and can assemble with any reservoir model. It will provide the advanced method for horizontal well to research reservoir engineering, the well completion and oil production design.