致密油藏分段多簇压裂水平井非稳态产能模型

针对段/簇间裂缝渗流场差异，基于线性流分区模型，考虑致密储层低速非达西流动和裂缝渗透率应力敏感特征，建立了致密油藏分段多簇压裂水平井非稳态产能模型。矿场实例验证了模型的正确性。模型计算分析显示：启动压力梯度主要影响油井的中后期产能，储层改造形成的复杂裂缝网络可有效降低非达西流动对油井前期产能的影响；裂缝渗透率应力敏感性对油井产油量影响较大，应力敏感系数越大，油井的产油量和累积产油量越低；裂缝总数较小时，裂缝的段簇比对累积产油量影响较大，相同裂缝条数下，段簇比越大，累积产油量越大；随储层改造体积增大，油井累积产油量增幅逐渐变缓。该研究结果可对致密油藏分段多簇压裂水平井产能评价提供理论依据。

Unsteady productivity model of segmented multi-cluster fractured horizontal wells in tight oil reservoir

Aiming at the difference of seepage field for fractures between segment and cluster,based on the linear flow zoning model,the unsteady productivity model of segmented multi-cluster fractured horizontal wells in tight oil reservoir was established,in which the effects of non-Darcy flow and stress sensitivity of tight oil reservoir were considered. The oilfield example verified the correctness validity of the model. The calculation of the model shows that the threshold pressure gradient mainly affects the productivity of oil wells in the middle and late stages,and the stimulated reservoir volume(SRV)formed by reservoir transformation can effectively reduce the impact of non-Darcy flow on the productivity of oil wells in the early stage. The fracture permeability stress sensitivity has great impact on oil well production. The greater the stress sensitivity coefficient,the lower the oil well production and cumulative production. When the total number of fractures is small,the segment-cluster ratio of fractures has a greater influence on the cumulative oil production. Under the same number of fractures,the larger the segment-cluster ratio,the greater the cumulative oil production. The cumulative oil production increase gradually slows down as the SRV increases. The results can provide theoretical basis for productivity evaluation of segmented multi-cluster fractured horizontal wells in tight oil reservoir.