考虑多段流动耦合的鱼骨刺井产能评价模型

根据实际油藏中鱼骨刺井井眼轨迹的三维空间展布特征,建立上下封闭边界油藏中鱼骨刺井生产段油藏渗流数学模型,考虑主井眼与分支井眼完井方式和井筒内流动损失,形成主井眼生产段井简内变质量管流、主井眼生产段近井油藏渗流、分支井眼生产段井筒内变质量管流和分支井眼生产段近井油藏渗流耦合作用的鱼骨刺井产能评价模型,并进行应用分析.结果表明:鱼骨刺井生产时,主井眼生产段沿程压降呈非线性增加,分支井眼与主井眼生产段交汇处存在压降突变点;主井眼与分支并眼生产段的势相互干扰,主井眼生产段径向流量分布呈两端高、中间低、交汇点处减小的特征,而分支井眼沿程径向流量呈跟端低、中间逐渐增大、指端高的特点.     

复杂结构井数值模拟分段耦合模型

针对复杂结构井的油藏渗流特征和井筒流动特点,分别建立油藏质量守恒方程、井筒质量守恒方程和井筒动量方程,采用井筒分段的方法对复杂结构井进行分段、编号,并与油藏网格相匹配,结合数值模拟矩阵"镶边"处理方法实现复杂结构井油藏和井筒的耦合,利用全隐式方法进行求解。以鱼骨状分支井为例进行计算分析。结果表明,复杂结构井分段耦合模型能够充分体现油藏渗流和井筒变质量流的相互影响,改进后的数值模拟软件可以满足复杂结构井生产动态模拟的需求。     

复杂结构井变质量管流与地层渗流耦合模型

基于井筒液体流动与管路液体流动的流动相似性,并综合考虑了不同完井方式下地层渗流、水平段变质量管流、弯曲段和垂直段多相管流之间的耦合作用,采用整体压力系统分析方法建立了不同完井方式(裸眼完井及射孔完井)复杂结构井地层渗流与变质量管流耦合模型.该模型可求解多分支井在考虑各分支间在主井眼井底相互干扰的情况下的协调产量与协调流压以及各分支在协调点的产量贡献和各分支水平段沿程压力分布及产量分布.此外,还模拟分析了射孔完井方式下三分支水平井自喷采油时的整体压力系统.结果表明,该模型对于多分支水平井不同完井方式下协调产量及协调压力的求解具有一定的指导意义.     

潜山裂缝性油藏鱼骨井开发效果影响因素分析

鱼骨井是多分支井的一种。裂缝性油藏中鱼骨井能沟通更多裂缝,增加与油藏的接触面积,提高油藏的渗流能力。针对某一裂缝性油藏,筛选出影响鱼骨井开发效果的井身结构参数。利用正交试验设计方法设计了9个试验方案,根据试验方案建立相应的油藏数值模拟模型。基于初期产能、累产油等开发指标,采用直观分析方法,得出影响鱼骨井开发效果的各井型参数的重要程度和最优的参数组合。四个影响因素显著程度依次是主井筒长度、分支间距、分支长度、分支角度;并通过单因素敏感性分析方法验证了相应的正交试验设计结果的准确性。     

复杂结构水平井产能关系研究

通过分析多底井油藏内的渗流特征,建立了复杂结构井的概念,并对影响复杂结构井的产能因素进行了正交数值实验研究.结果表明,分支水平井的分支长度和分支井数是影响产能的主要因素,二者的影响程度相当,增加分支长度或分支井数均可以增大泄油范围,进一步增加油井产能.有限导流条件下复杂结构水平井的产能关系呈非线性特征,不同分支井条件下的产能增比与分支井数和分支长度组合数呈指数变化特征.复杂结构井的产能关系式能够涵盖常规水平井,具有水平井产能关系的一般性特征.     

委内瑞拉奥里诺科泡沫油油藏多分支井加密方式研究

针对委内瑞拉奥里诺科泡沫油油藏部分油井出现了产量递减加快、生产气油比升高的问题,通过加密多分支水平井以延长冷采时间.以5组分2动力学方程泡沫油模型反映泡沫油油藏渗流机理,以室内实验相态和压力衰竭实验拟合确定泡沫油组分性质参数与泡沫油相渗曲线,建立了泡沫油油藏数值模拟模型,进而研究了泡沫油油藏多分支水平井加密方式.研究表明:上述方法可较好地模拟泡沫油油藏生产特征;多分支水平井加密原有井网可以改善油藏开发效果,最佳加密方式为水平方向加密2口主井筒长900 m、分支间距300 m、分支长度210 m、分支数为2的多分支水平井,垂直方向加密2口井筒长300 m、分支间距180 m、分支长度210 m、分支数为4的多分支水平井.     

复杂结构水平井产能关系研究

通过分析多底井油藏内的渗流特征，建立了复杂结构井的概念，并对影响复杂结构井的产能因素进行了正交数值实验研究。结果表明，分支水平井的分支长度和分支井数是影响产能的主要因素，二者的影响程度相当，增加分支长度或分支井数均可以增大泄油范围，进一步增加油井产能。有限导流条件下复杂结构水平井的产能关系呈非线性特征，不同分支井条件下的产能增比与分支井数和分支长度组合数呈指数变化特征。复杂结构井的产能关系式能够涵盖常规水平井，具有水平井产能关系的一般性特征。     

低渗透油藏多分支裂缝压力动态分析

复合应用水力压裂和高能气压裂等多种压裂改造技术开采低渗透油藏,在近井地带形成不受地应力控制的多分支裂缝。基于渗流理论和叠加原理,分析了未穿透储层的多分支裂缝的渗流规律,再利用Green函数和Newman乘积法求得其地层压力解析解,这是一种新的计算多裂缝地层压力的方法,可避免复杂的推导过程。研究表明:未穿透储层的多分支裂缝的井底压力随渗透率、孔隙度的增大而减小,但减小的幅度逐渐减小,且地层渗透率对井底压力的影响更明显;裂缝长度越长,相邻裂缝长度差距越小,裂缝分布越不均匀,裂缝间相互干扰作用越严重。所以在一定经济范围内,裂缝长度存在最优值,裂缝分布越均匀改造效果越好。该研究成果对油气藏的压裂改造设计具有实际指导意义。     

油藏各向异性对鱼骨状分支井产能影响分析

为了研究油藏各向异性对鱼骨状分支井产能的影响,基于空间变换理论将各向异性渗透率空间转换为各向同性渗透率空间,并应用鱼骨状分支井渗流模型进行产能预测。结果表明:油藏各向异性会导致鱼骨状分支井等压线分布发生明显偏转,各向异性程度越大,偏转越明显;水平面内垂直于主井筒方向的渗透率对鱼骨状分支井产能起决定作用,水平面内平行于主井筒方向的渗透率起次要作用;当水平面内渗透率各向异性较为明确时,应选择主井筒方向与最大渗透率方向垂直;当水平面内渗透率各向异性不明确时,选择的分支角度越大,越能消除水平面内渗透率各向异性不确定性带来的影响。     

辐射状分支井产能电模拟实验研究

依据相似原理,采用电模拟试验装置,设计了辐射状分支井模型.研究了在不同分支数、分支水平段长度时,辐射状分支井井筒附近的压力分布,描述油藏中的压力场形态,评价各种参数对产能的影响,为水平井产能预测提供了依据.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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