【作者】 谷建伟；

【导师】 翟世奎；

【作者基本信息】 中国海洋大学 ， 海洋地质， 2005， 博士

【摘要】 在分析不同尺度油藏动态研究方法的特点基础上，指出处于高含水开发期间的油藏需要将微观研究与宏观研究相结合来得到此时地下流体的分布规律。通过分析微观油水运动机理，指出稳定法和不稳定方法测量的油水相对渗透率曲线是一种宏观上的统计规律，没有考虑岩石微观特征对油水运动分布规律的影响，不适用于油藏高含水开发期间描述地下油水分布规律。同时指出了经典数值模拟计算中出现的各种问题，并分析了造成这些问题出现的原因。 指出利用孔隙网络模型可以计算出基于微观孔喉特征的相对渗透率曲线，再和经典油藏数值模拟技术相结合，可以得到基于微观渗流机理的宏观油藏数值模拟方法。采用逾渗理论和孔隙水平网络模型，导出了不同润湿体系和饱和历史下的逾渗可进入度、逾渗临界值、有效分数和相导流能力的具体表达形式。利用截面为等边三角形的棱柱管代替以往网络模型中采用的圆管，更细致地描述了岩石的润湿性影响和微观油水分布特征。采用Bethe网络计算了油水相对渗透率规律，并分析了微观特征参数对相对渗透率的影响，计算结果分析表明该方法可行。 对考虑启动压力下的一维油水动态进行了推导，扩展了该方法的适用范围，可以用于低渗透油藏动态的计算，分析了重力、毛管压力和启动压力的存在对油藏动态参数的影响规律。建立了考虑微观渗流特征的油气水三维三相渗流的数学模型，采用差分离散方法形成数值模型；讨论了由于网格加密和死节点消除给系数矩阵造成的影响；给出利用数值模拟结果计算油藏开发指标的方法；利用预处理共轭梯度正交极小化方法求解方程组，并编制了相应地计算软件。 与经典的数值模拟方法相比，基于微观渗流机理的宏观数值模拟计算方法主要的优点是考虑了油藏不同部位由于微观孔喉结构分布不同导致地油水渗流规律的改变，并可以得到剩余油在不同孔喉空间中的分布形式和规律，实现了利用黑油模型即可以为调剖堵水、化学驱等提高采收率措施提供决策依据。此外该模型中还可以考虑的问题有:不同孔喉分布采用不同的油水渗流关系;网格加密和死节点消除的新方法;原油粘度和地层的渗透率随开发过程的变化;波及系数;计算剩余油储量丰度、可采储量丰度、单井控制储量、单井控制可采储量;水淹状况等参数。最后利用该模型对胜利油区的某油藏区块进行了计算，利用取心资料分析计算不同部位的相对渗透率曲线，讨论了运用过程中的处理方法。对区块计算结果进行了分析，对涉及到的问题进行了验证，结果表明计算过程稳定，考虑问题全面，可以为现场决策提供丰富的结果信息。关键词:高含水开发期;网络模型;逾渗理论;微观渗流机理;宏观油藏数值模拟;剩余油分布形式更多还原

【Abstract】 After analyzing different scale reservoir development methods, the paper indicates that study based on micro seepage mechanism and macro reservoir simulation should be used to calculate liquid distributing features during high water-cut development period. By studying micro seepage mechanism of water and oil, the paper shows that the relative permeability curve measured in reservoir physics lab by steady or unsteady method is a macro statistical regularity, which doesn’t allow for the influence of micro rock features on liquid flow rules, so the relative permeability curve measured in reservoir physics lab is not applicable to describing water and oil distribution in reservoir during high water-cut development period. At the same time, the paper indicates some questions of classical reservoir simulation, finds out reasons that result in those questions.Pore-level network model can be used to calculate the relative permeability curve based on micro throat and hole features and if it could be combined with classical reservoir simulation technique, the macro reservoir numerical simulation method based on micro seepage mechanism will be accessible. According to percolation theory and pore-level network model, the calculating formulae of accessible fraction, critical percolation value, effective fraction and phase equivalent conductivity in different wet systems and displacement processes are derived in dissertation. Substituting prismatic tube with equilateral triangle section for ancient tube with circular section is favorable for describing rock wetting characteristics and calculating micro liquid distributing features. The relative permeability curves are worked out by Bethe network model, at the same time the influence of micro characteristics on curves are analyzed. The analyzing results prove the method feasible.The 1D reservoir developing method with starting pressure is put forward, which enlarges applicable range and which analyzes the influence of gravity, capillary, starting pressure on reservoir performance parameters. . The three -dimension and three -phasemathematical model of water, oil and gas are established, which takes micro seepage mechanism into account. The difference method is used to get numerical equations, the equations are solved by conjugating pretreatment grads orthomin method, at the same time the influences of grid refinement and dead node elimination on coefficient matrix are discussed, the methods to calculating development indexes are put forward. According to the solving method, the computer program is compiled and completed.Compared with classical reservoir simulation, the most important advantage of macro reservoir simulation based on micro seepage mechanism is that the oil and water relative permeability changes because of different micro throat and hole distribution features in reservoir are taken into account. By this improvement, the distributing rules and form of remaining oil in reservoir pore can be described clearly. It become a reality that black oil mathematical model could provide decision making explanations for profile controlling, water plugging, chemical flooding and other enhanced oil recovery(EOR) methods. In addition, the model has other merits, for example, adopting different relative permeability curves in different formation, the new way to refine grid and to eliminate dead node, dealing with the changes of permeability and oil viscosity in different development period. The following parameters can be gained through analyzing simulation result: sweep efficiency, remaining oil reserves abundance, recoverable reserves abundance, controlling reserves by single well, recoverable controlling reserves by single well, water-flooded area, and so on. At last, the model is tested by one reservoir block in Sheng-Li petroliferous area, the different relative permeability curves in different parts of reservoir are worked out by network model and the method to deal with permeability is discussed. The results are analyzed, the merits mentioned are also tested. The analyzing resu更多还原