二级裂缝倾角对复杂缝网中支撑剂输送的影响  

Effect of secondary fracture dip on proppant transport in complex fracture network

作　　者：张艳博 徐加祥 刘哲 马欧 杨立峰[2] 高睿 高乐天 那迪尔·肉孜买买提 ZHANG Yanbo;XU Jiaxiang;LIU Zhe;MA Ou;YANG Lifeng;GAO Rui;GAO Letian;Nadier Rouzimaimaiti(College of Petroleum Engineering,Liaoning Petrochemical University,Fushun 113001,China;Fracturing and Acidifying Service Center of Research Institute of Petroleum Exploration&Development,Beijing 100083,China;Korla Drilling Engineering Company of CNPC Bohai Drilling Engineering Co Ltd,Korla 841003,China)

机构地区：[1]辽宁石油化工大学石油天然气工程学院,辽宁抚顺113001 [2]中国石油勘探开发研究院压裂酸化技术服务中心,北京100083 [3]中国石油渤海钻探工程有限公司库尔勒分公司,新疆库尔勒841003

出　　处：《大庆石油地质与开发》2023年第1期91-99,共9页Petroleum Geology & Oilfield Development in Daqing

基　　金：辽宁石油化工大学大学生创新训练项目“复杂缝网中低黏滑溜水携支撑剂运移模拟研究”(2021101480244);辽宁石油化工大学引进人才科研启动基金项目“非常规油气储层改造支撑剂运移及开发效果研究”(2020XJJL-018);中国石油天然气集团有限公司科学研究与技术开发项目“体积压裂优化设计软件”(2020B-4118)。

摘　　要：支撑剂在复杂缝网中的分布情况直接决定了非常规油气的开发效果。为了探究体积压裂后复杂缝网中二级裂缝倾角对其支撑剂输送特征的影响,建立了可以改变二级裂缝位置和倾角的缝网模型。在分析携砂液在缝网内流动的基础上,建立了支撑剂在复杂缝网中的输送模型,并以曳力、弹性碰撞模型和Knudsen余弦散射定律分别表征支撑剂与携砂液、支撑剂颗粒间以及支撑剂与粗糙裂缝壁面的相互作用。数值模拟结果表明:改变二级裂缝倾角和位置,会严重影响缝网中主裂缝和二级裂缝内支撑剂的铺置情况;当二级裂缝水平时,其中的支撑剂分布范围最小,而增大二级裂缝到主裂缝入口的距离可以有效改善支撑剂在主裂缝中的分布;在二级裂缝垂直的缝网中支撑剂填充比例最大,当二级裂缝倾角为90°~120°时,支撑剂填充效果最差。研究成果为体积压裂中携砂液及缝网优化设计提供了理论指导。Proppant distribution in complex fracture network directly determines the development of unconventional oil and gas.In order to investigate the influence of secondary fracture dip on proppant transport in complex fracture network after volume fracturing,a fracture network model which can change the location and dip of secondary frac-tures is established.Based on analysis of slurry flowing in fracture network,transport model of proppant in complex fracture network is established,and interactions between proppant and slurry,among proppant particles and be-tween proppant and rough fracture surface are characterized by drag force,elastic collision model and Knudsen cosine scattering law.Numerical simulation shows that changing the dip and location of secondary fractures may seri-ously affect the placement of proppant in main fracture and secondary fractures respectively.When secondary frac-ture is horizontal,the distribution area of proppant is the smallest,and increasing the distance from secondary frac-ture to the inlet of main fracture can effectively improve the distribution of proppant in main fracture.Proppant fill-ing proportion is the largest in fracture network with vertical secondary fractures.When the dip of secondary frac-tures is 90°~120°,proppant filling effect is the worst.This study provides guidance for optimization of fracture net-work and slurry in volume fracturing.

关 键 词：非常规油气 水力压裂 复杂缝网 支撑剂输送 粒子追踪 

分 类 号：TE357[石油与天然气工程—油气田开发工程]