辐射流动条件下粗糙圆盘裂隙中浆-水两相流特征

裂隙灌浆是处理坝基工程地质问题的重要手段,而现有的裂隙灌浆研究常忽略了水相对浆液扩散过程的影响,不能真实反映浆液侵入过程。为了准确地模拟坝基裂隙灌浆过程,采用相场法分析了裂隙介质中浆液侵入特征,构建了考虑水相作用的粗糙圆盘裂隙数值模型,分析了裂隙粗糙度、裂隙开度、灌浆速度、灌浆压力对辐射流动条件下浆液侵入特征的影响。研究结果表明:恒定灌浆速率条件下,相界面移动速率随时间逐渐减小;粗糙凸起体会引起黏性耗能,导致粗糙圆盘孔口压力显著大于光滑圆盘;恒定灌浆压力条件下,提高灌浆压力比延长灌浆时间更加有效,开度越小浆液侵入量越小;灌浆驱水效率不仅受粗糙度大小的影响,还与凸起体的分布相关;灌浆孔附近的粗糙凸起体引起的剪切速率扰动大于远场的。

渤海湾盆地东濮凹陷文留构造发育特征与气藏形成

文留构造是Es3(2) Es2期间在中央隆起带背景上因盐聚集而形成的背斜构造,构造翼部因盐滑塌而使圈闭幅度加大。C-P煤系因埋深加大而进入二次生气期,并在约4000m发生初次运移。烃源岩的主体埋深5200～6300m,位于文东和前梨园地区。煤成气以微裂缝-裂隙(断层)网络为主要通道向中央隆起带运移,并在东营运动(Ⅱ幕)期达到最大规模。天然气进入圈闭后,首先充注Es4(3-5)段Ⅰ类和Ⅱ类储层(驱水效率73%～56%),后随着气柱加大驱替压力增加而向Es4(1-2)和Es4(7-8)Ⅲ类储层中扩散,最终驱水效率约为40%。

Geochemical characteristics of reservoir after water and polymer flooding in Xingshugang oilfield of Daqing

Collecting 44 oil-sand specimens of Pu-I Member in two inspection wells before and after polymer flooding in the thirteenth district of Xingshugang oilfield,with experimental analysis,the author obtained the data about oil viscosity,flow,oil saturation and oil displacement efficiency.The result shows that viscous oil predominates in the main remaining oil in Xingshugang oilfield after water flooding with a certain amount of low viscosity oil,high viscosity oil and heavy oil;after polymer flooding,the viscous oil is main ingredient.Compared with water flooding,the low mobility and poor oil can be spread by polymer flooding,expanding the affected area and improving sweep efficiency and oil recovery.The geochemical affecting factors of water flooding and oil displacement efficiency refer to reservoir flow,permeability and the viscosity of residual oil.In the reservoir with permeability from low to high,the polymer flooding efficiency is better than water flooding.It provides the basis for improving the water and polymer flooding efficiency of the Xingshugang oilfield.