一种新的底水油藏鱼骨分支水平井耦合模型

针对底水油藏鱼骨分支水平井的产能预测和井筒压力分布问题，开展了分支水平井井筒与油藏渗流的耦合模 型研究。研究利用底水油藏下边界恒压供给的特点，采用微元思想，用储层细分的方法代替井筒细分的处理方法，建 立了底水油藏鱼骨分支水平井储层渗流与井筒流动的耦合模型。对储层微元细分处理属于一类新的微元处理方法和 研究手段，由此获得的简化耦合模型求解产能和压降剖面时可大幅减小计算量，节约计算成本。简化模型的计算结果 符合精确模型的基本规律和认识，同时给出了简化模型向精确模型修正的比例，按此比例修正后的简化模型进行产能 的快速估算是一种实际可行的简便方法，为底水油藏鱼骨分支水平产能预测，为进一步计算延缓底水上升的临界产 量、临界压差等参数提供了研究基础。

A Coupling Model of Fishbone Multilateral Horizontal Well in Bottom Water Reservoir

In order to solve the problems of productivity prediction and pressure distribution of herringbone branched horizontal wellbore in bottom water reservoir，a coupling model of multilateral horizontal well and seepage flow in the reservoir is investigated. Based on characteristics of the constant pressure supply boundary condition and micro-unit method，by subdividing the reservoir rather than subdividing the well bore，a new coupling model of herringbone branched horizontal well in bottom water reservoir is established. Subdivision of the reservoir is a new resolution type of micro-unit treatment and research method. The obtained simplified model greatly decreases the calculation work and compute cost when productivity and pressure drop profile are calculated. The results of the simplified model accord with the basic principles of accurate model. Meanwhile this paper proposes the modified ratio of simplified model transferring to the accurate model. It′s an effective and convenient way to apply the simplified model modified by this ratio to do the rapid evaluation of productivity. Moreover the simplified model provides the research basis for productivity prediction of herringbone branched horizontal well in bottom water reservoir. And it contributes to the further calculation of parameters like critical production and critical pressure drop to delay the occurrence of bottom water breakthrough.