鄂尔多斯盆地中生界开发层系均为低压油藏,注水开发是低渗透油藏提高采收率、提高开发效益的有效手段,是低渗透油藏实现长期稳产的根本保证。以控制吴仓堡地区长6低渗透油藏含水上升速度,减缓递减,实现长期稳产为目的,分析了精细注采调控技术在吴仓堡长6油藏的应用效果,并进一步对区内开发存在的问题和下步与开发相关的研究提出了建议。

Development strata of the Paleozoic in the Ordos Basin are low-pressure reservoir, and water injection development is a low-permeability reservoir enhanced oil recovery and effective means to improve development effectiveness, and low permeability reservoir to achieve the fundamental guarantee of long-term stability. For Chang 6 low permeability reservoir of Wucangpu block, for the purpose of slowing down the water cut ascending velocity and the production decline rate, sustaining production for long term, this paper analyses the application result of accurate modification and con- trol technology of injection and production in Chang 6 reservoir of Wucangpu block. Further development exists in the region and the next step of development is recommended.

水驱曲线在低渗油藏中直线段的出现时间要早于中高渗透油藏，无疑加大了水驱特征曲线在低渗油藏的应用范围。而地层原油黏度是影响油藏含水上升规律的天然因素之一，对于水驱特征曲线具有选择性。尝试推导了利用丁型水驱特征曲线计算低渗低黏度油藏相对渗透率曲线的公式，给出了具体的计算实例，并进行了讨论。认为该方法得到的相对渗透率对于低渗低黏度油藏是具有代表性的，能满足一定的精度要求，具有一定的实用性。

Straight line segments of water drive curves in low permeability reservoirs appear earlier than in middle and high permea-bility reservoirs. For this reason, water drive curve has found an increasingly wide utilization in low permeability reservoirs. Further-more, oil viscosity is one of the natural factors on water raising law of reservoirs and affects the choice of water drive curves. By us-ing type IV water drive characteristic curve, this paper derived the formula for computing relative permeability curve of low permea-bility and viscosity reservoirs, gave the specific calculation examples and discussed them. Calculation results showed that the rela-tive permeability is typical with certain accuracy and practical value.

考虑流体在低渗透油藏流动过程中启动压力梯度的影响,建立了三维油水两相油藏数值模拟数学模型;基于拟稳定渗流理论,推导了考虑启动压力梯度影响的油藏数值模拟定井底压力、定产油量和定产液量条件下的内边界条件;通过全隐式差分格式建立了低渗透油藏数值模拟数值模型,并采用预处理共轭梯度法进行了求解。计算结果表明,启动压力梯度对低渗透油藏的压力场有明显的影响,定产条件下,启动压力梯度越大则压力变化越剧烈,压降的影响范围越大。井–网格条件对油藏压力场的影响不明显,但对井底压力影响较大,定产条件下,启动压力梯度越大,则井底流压越低。

A mathematical model for numerical simulation of 3D water-oil two phase reservoir is established with consideration of the influence of start-up pressure gradient,and the inner boundary conditions are derived based on the pseudo stable seepage theory,in the process of which fixed flow pressure,fixed oil production rate and fixed liquid production rate are taken into consideration. Then by full implicit finite difference scheme,corresponding numerical model is established and solved by pretreatment conjugate gradient method. The calculation results show that start-up pressure gradient has obvious effect on pressure field in low permeability reservoirs;in case of fixed oil production,the bigger start-up pressure gradient is,the more severely pressure changes and the larger pressure drop range is. The effect of well-grid conditions on pressure field is not obvious,but its effect on well flow pressure is obvious;in case of fixed oil production rate,with the increase of start-up pressure gr

以裂缝各向异性全张量渗透率动态耦合渗流模型为基础,建立三维三相裂缝各向异性特低渗透油藏流固耦合数学模型,并运用模块化显示耦合迭代求解建立流固耦合渗流数值模拟方法,编制耦合求解程序.研究表明：对于裂缝性油藏,随着油藏开采过程中压力的变化,岩石变形和储层介质的各向异性应变特性使开发过程中多组裂缝的变形程度不同,引起裂缝渗透率的非线性变化,进而使油藏裂缝渗透率张量主值发生旋转,改变液流方向、影响油藏开发效果.

With dynamic coupling model of fractured anisotropic full-tensor permeability, a complete three-dimensional three-phase fluid-solid coupling model for anisotropic ultra-low permeability reservoir is established. Using modular explicit coupling iteration, we establish a fluid & solid coupling seepage numerical simulation method considering fracture deformation and corresponding coupling program. It shows that for fractured reservoir, with change of reservoir pressure in process of mining, rock deformation and anisotropy of reservoir medium strain can make various deformation degree in multiple sets of cracks, cause nonlinear change of fracture permeability, which makes principal value of reservoir fracture permeability tensor rotating, changing flow direction, affecting reservoir development effect.

为了综合反映启动压力和应力敏感对低渗透油藏开发规律的影响，首先，通过室内实验研究低渗透岩芯启动压力梯度和应力敏感效应，并建立启动压力梯度和动态渗透率的动力学模型；在此基础上，根据质量守恒定律和渗流力学理论，建立同时考虑启动压力和应力敏感效应的低渗透油藏油水两相渗流数学模型，据此研制低渗透油藏水驱数值模拟软件；然后，利用该软件研究不同特征对渗流场、开发规律的影响以及启动压力和应力敏感对开发效果的影响；最后，研究超前注水、增大注采比、增大注采速度对采收率的影响规律，并优化最佳注入参数。研究结果表明，启动压力梯度是低渗透油藏采收率较低的直接原因，应力敏感通过强化启动压力梯度的方式间接影响采收率；超前注水、增大注采比和增大注采速度均可以提高低渗透油藏采收率，提高幅度为：超前注水＞增大注采比＞增大注采速度；最佳超前注水时间为100 d，最佳注采比为1.1∶1，最佳注入速度为0.00015～0.00025 PV/d。

In order to reflect the influences of starting pressure and stress sensitivity on the development law of low-permeability reservoirs,the following researches are conducted. Firstly,the dynamics models of threshold pressure gradient and dynamic permeability are established based on the experimental results of threshold pressure gradient and stress sensitivity effects. Based on this,the mathematical model of water-flooding in low-permeability reservoir with considering the starting pressure and stress sensitivity is established according to the law of conservation of mass and permeation fluid mechanics theories. Also,the corresponding numerical simulation software is developed. Then,the software is used to study the influences of different features on the seepage field and development law,and the effects of starting pressure and stress sensitivity on development effect. At last,the influences of advanced water flooding,increasing injection-production ratio and increasing injection-produc