非均质底水油藏水平井ICD完井耦合模型与目标剖面计算方法

入流控制装置(Inflow Control Device,ICD)近年来在水平井分段完井中应用日益广泛,但目前针对ICD完井建立的半解析耦合模型无法准确反映水平井端部效应,在ICD优化设计过程中对于目标入流剖面的选择缺乏依据。为此,首先引入了基于势的叠加原理和镜像反射原理的油藏渗流模型用以准确反映水平井入流特征,建立了适用于非均质底水油藏水平井ICD完井的稳态耦合模型;之后考虑油井不同的生产制度,给出了非均质油藏水平井ICD完井优化目标入流剖面的确定方法,并以喷嘴型ICD为例对ICD设计流程进行了具体描述,对最优非均匀ICD和最优均匀ICD计算结果进行了对比分析。结果表明:ICD优化设计与生产制度有很大关系,均匀入流剖面并非总是理想的入流剖面;非均匀ICD控流效果要优于均匀ICD,但均匀ICD完井对井底流压有较宽的适应性;高生产压差有助于发挥喷嘴型ICD的控流优势。

Calculation method for ICD completion coupling model and target proifle of horizontal wells in heterogeneous bottom water reservoir

The Inflow Control Device (ICD) has been increasingly used in staged completion of horizontal wells in recent years. However, the semi-analytical coupling model built for ICD completion cannot accurately reflect the end effect in horizontal wells, and there is a lack of basis for the selection of target inflow profile during ICD optimization design. Therefore, a reservoir seepage model was first introduced based on potential superposition principle and specular reflection principle to accurately reflect the inflow features of horizontal wells, and a steady state coupling model was built which was suitable for ICD completion of heterogeneous bottom water reservoirs. Thereafter, in view of different production systems of oil wells, this paper provides the determination method for optimized target inflow profile of horizontal wells in heterogeneous reservoirs completed with ICD, describes in detail the design procedure of ICD taking nozzle-type ICD as an example and compares and analyzes the calculation results of optimal non-uniform ICD and optimal uniform ICD. The result shows that the optimized design of ICD is closely related to production system and uniform inflow profile is not always the ideal inflow profile. The flow control effect of non-uniform ICD is superior to that of uniform ICD, but well completion with uniform OCD is more widely adaptable to the bottom hole flow pressure. The high production pressure difference helps bring to play the flow control advantage of nozzle-type ICD.