低渗透断块油藏水动力学场特征及注水开发方式研究

发布时间：2018-01-16 12:21

本文关键词：低渗透断块油藏水动力学场特征及注水开发方式研究　出处：《西南石油大学》2015年硕士论文　论文类型：学位论文

【摘要】：低渗透断块油藏不仅具有常规断块油藏注采井网不完善、边界条件复杂、油水系统复杂的共同特点,同时还具有低渗透油藏的非达西渗流、油井自然产能低需要实施压裂增产措施、地层压力下降快需要及时注水补充地层能量的特征。因此,如何有效或高效开发低渗透断块油藏需要充分论证注采系统的有效性、注采井网的适应性和完善性。本文针对不同类型的低渗透复杂断块油藏,以二参数非线性渗流模型为基础,考虑人工裂缝和复杂边界对渗流场特征的影响,综合采用油藏工程、渗流力学、复变函数理论及计算机编程等多学科交叉的方法,研究了低渗透复杂断块油藏渗流特征,分析了不同影响因素对压裂井产能的影响,并在理论研究的基础上通过数值模拟技术针对不同类型的低渗透复杂断块油藏进行了注水开发技术的优化研究,取得了以下研究成果： (1)以二参数非线性渗流模型为基础,考虑非线性渗流对油井产能的影响,通过matlab编程求数值解获得了不同流度、不同产量和对应压差条件下的极限注采井距图版；利用复变函数理论通过两次保角变换把W平面上任意裂缝方向的生产井变换为W,平面上带宽为π的排液坑道,分析了压裂井采油直井注水一注一采渗流规律,探讨了人工裂缝方向与极限注采井距和注采压差的匹配关系； (2)利用comsol仿真模拟软件建立了考虑复杂边界条件下的单相稳定渗流模型,以断层夹角为45。的三角形低渗透断块油藏和定压边界的半圆形低渗透断块油藏为例,研究了复杂边界和人工裂缝共同影响下的渗流场特征,分析了不同影响因素对断块可动用面积的影响；以拟稳定试井产能公式为基础,同时考虑复杂边界和人工裂缝的影响,分析了裂缝导流能力、裂缝半长、形状因子和表皮系数对压裂井产能的影响,并获得了最优裂缝参数； (3)通过对三角形低渗透断块油藏不完善井网条件下的数值模拟优化研究,获得了人工裂缝与不完善注采井网的最优匹配关系和最优注水方式；通过对条带状低渗透断块油藏不完善五点压裂井网的正交优化模拟,得到了适合于条带状低渗透断块油藏的注采模式及最优的人工裂缝方向分布,且不同影响因素对原油采收率的影响程度为：井网形式人工裂缝方向人工裂缝半长； (4)针对不同边水强度的半圆形低渗透断块油藏,通过对比不同井网形式、不同裂缝方向和不同注水方式对开发效果的影响,分析了不同影响因素对水驱面积波及效率和采收率的影响,从不同的考虑角度给出了适合于不同边水强度条件下的注水开发方式。
[Abstract]:Low permeability fault block reservoirs not only have the common characteristics of imperfect injection-production pattern, complex boundary conditions and complex oil-water system, but also have non-Darcy percolation in low permeability reservoirs. Low natural productivity of oil wells need to implement fracturing measures to increase production, and rapid reduction of formation pressure needs timely injection to replenish the characteristics of formation energy. How to develop low permeability fault block reservoir effectively or efficiently needs to fully demonstrate the effectiveness of injection-production system and the adaptability and perfection of injection-production pattern. In this paper, for different types of low-permeability complex fault-block reservoirs, based on two-parameter nonlinear percolation model, considering the effects of artificial fractures and complex boundaries on the seepage field characteristics, reservoir engineering and percolation mechanics are adopted synthetically. The percolation characteristics of complex fault block reservoirs with low permeability are studied by using the theory of complex variable function and computer programming, and the influence of different factors on the productivity of fracturing wells is analyzed. On the basis of theoretical research, the optimization of water injection development technology for different types of complex fault block reservoirs with low permeability is studied by numerical simulation technology. The following research results are obtained: 1) on the basis of two-parameter nonlinear seepage model, considering the influence of nonlinear seepage on oil well productivity, the numerical solution of different mobility is obtained by matlab programming. The limit injection-production distance chart under the condition of different production rate and corresponding pressure difference; By using the theory of complex variable function, the production well with arbitrary fracture direction in W plane is transformed into a fluid discharge tunnel with a bandwidth of 蟺 on the plane by means of two conformal transformations, and the law of water injection, injection and production percolation in the straight well of fracturing well is analyzed. The matching relationship between the direction of artificial fracture and the interval between injection and production and the pressure difference between injection and production is discussed. 2) the single-phase steady seepage model considering complex boundary conditions is established by using comsol simulation software. Taking triangular low permeability fault block reservoir with an angle of 45. And semicircular low permeability block reservoir with constant pressure boundary as an example, the seepage field characteristics under the influence of complex boundary and artificial fracture are studied. The influence of different factors on the usable area of fault block is analyzed. Based on the quasi-stable well test productivity formula and considering the effects of complex boundaries and artificial fractures, the effects of fracture conductivity, fracture half-length, shape factor and skin factor on the productivity of fracturing wells are analyzed. The optimum fracture parameters are obtained. 3) the optimal matching relation and water injection mode of artificial fracture and imperfect injection-production well pattern are obtained through the numerical simulation and optimization research on the condition of imperfect well pattern in triangular low permeability fault block reservoir. Through the orthogonal optimization of the imperfect five-point fracturing well pattern in the strip low permeability fault block reservoir, the injection and production pattern and the optimal artificial fracture direction distribution of the strip low permeability fault block reservoir are obtained. The degree of influence of different factors on oil recovery is as follows: the artificial fracture in the pattern of well pattern is half long in the direction of artificial fracture; In view of the semicircular low permeability fault block reservoir with different edge water intensity, the effect of different well pattern, different fracture direction and different water injection mode on the development effect is compared. The influence of different factors on water flooding area sweep efficiency and oil recovery is analyzed, and the water injection development methods suitable for different edge water intensity conditions are given from different points of view.
【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE348

【参考文献】