油套环空和空心抽油杆掺化学剂抽油井举升工艺计算模型

针对稠油井井筒流体流动难的特点 ,利用节点系统分析方法 ,建立了空心抽油杆和油套环空掺化学剂的抽油机井举升工艺计算模型 ,并研究利用化学方法改善井筒流体流动的条件。结果表明 ,M型化学剂通过乳化和热力降粘作用可改善流体的流动性和抽油杆柱的受力状况 ;在启动过程中掺入化学剂的温度对油井生产有一定的影响。     

基于分布式光纤声波监测数据和机器学习的井筒流体类型识别方法

基于建立的实尺寸水平井筒流体流动光纤监测模拟试验系统,开展油气水流动模拟试验,获得不同流体流动情况下的分布式光纤声波监测(DAS)数据;利用小波时间散射变换和短时傅里叶变换对DAS数据进行处理,提取流体流动特征,建立基于机器学习的井筒流体类型识别分类方法。结果表明：融合低方差散射特征和短时时频特征数据能提高流体类型识别的准确率,并且随机森林算法的识别结果优于BP神经网络和决策树;该方法为井筒多相流体流动识别提供了一种新的技术手段。     

井筒重力热管室内实验与矿场试验研究

利用重力热管的高效传热特性,将其应用在井筒流体加热过程中,分析了重力热管加热效果的外部影响因素。结果表明,重力热管在不消耗额外能量的条件下,利用深部流体能量提高井筒上部流体的温度,能起到均衡井筒温度场的作用,进而改善井筒温度分布剖面。室内实验表明：工质类型、工质充液率、真空度对重力热管的传热效果有很大影响。矿场试验表明：在适当的条件下,能够将原油温度加热到原油凝点以上,降低原油粘度,改善原油流动性,井底抽油杆载荷,满足生产实际的要求;重力热管加热过程受井底温度、热管下入深度、油井产液量以及原油物性等因素的影响,随着井底温度、热管下入深度、油井产液量的增加,重力热管的传热效果变好。     

超稠油双管泵下掺蒸汽井筒加热降粘举升工艺

根据传热学和两相流原理,建立了超稠油双管泵下掺蒸汽井筒加热降粘举升过程中蒸汽与产液沿井筒传热与流动的热力学模型。计算了蒸汽与产液沿井筒的温度分布和压力体质了抽油杆柱受力分析与抽油杆柱设计。     

水平井筒变质量流体流动实验研究

设计并建立了水平井筒变质量流体流动的模拟实验装置,对具有射孔完井的水平井筒变质量流动特性进行了实验研究。利用先进的数据采集系统获最了大量的实验数据。对水平井井筒单孔眼段流体的流动阻力损失分析可知,流动阻力由三部分组成：管壁摩擦阻力、加速损失和混合损。     

射孔水平井孔眼分布优化研究

利用油藏流体渗流模型和水平井筒内流体流动模型 ,推导出了油藏井筒流体流动耦合模型 ,在该模型中考虑了两种流动的相互作用和影响。建立了以水平井产量为目标函数、以孔眼分布为决策变量的优化模型 ,将其计算结果与均匀流入剖面、均匀射孔分布的结果进行了对比。由于优化模型中考虑了水平井筒内变质量流的影响 ,从而可为现场水平井的优化设计提供理论依据。     

重力热管伴热改善稠油井井筒传热损失的研究

根据重力热管作用原理,结合井筒传热过程,建立了稠油生产井中采用热管伴热方式时井筒热损失的计算模型,利用该模型分析了重力热管改善井筒热损失的原理。在此基础上,讨论了主要工艺参数对热管井井筒热损失的影响,结果表明：随着井底温度升高、产液量增加、热管下入深度加深,井筒热损失增大,其中,产液量对热损失的影响尤为显著。现场试验及理论研究表明：在不消耗额外能量的前提下,重力热管能够利用深部流体自身的能量提高井筒上部流体的温度,降低传热过程中的热损失,进而改善井筒温度分布剖面。该方法可以减小产出液在井下管道上升过程中的流动阻力,从而降低抽油机的负荷,实现低能耗对井筒流体加热的目的。     

井筒重力热管流动与传热特性的研究

井筒重力热管是利用热管将油藏自身能量,即井底热量传递到井筒上部,在无需外加动力条件下实现对井筒近井口流体加热,改善井口流体温度分布,防止近井口结蜡和絮凝,从而降低采油成本。为了研究井筒重力热管的传热性能和工作过程,进而改进和优化重力热管的传热性能,建立了重力热管内部流动和传热的数学模型。利用该模型对重力热管的传热特性进行了数值模拟,得到了热管正常工作时,液膜厚度、蒸汽流速和液膜流速及热管换热系数随热管高度的变化规律。     

射孔水平井孔眼分布优化研究

利用油藏流体模型和水平井筒内流体流动模型，推导出了油藏－井筒流体流动耦合模型，在该模型中考虑了两种流动的相互作用和影响。建立了以水平井产量为目标函数、以孔眼分布为决策变量的优化模型，将其计算结果与均匀流入剖面、均匀射孔分布的结果进行了对比。由于优化模型中考虑了水平井筒内变质量流的影响，从而可为现场水平井的优化设计提供理论依据。     

射孔完井水平井筒变质量湍流压降规律研究

运用拟三维原理 ,提出了用于计算地层刚性渗流、弹性不稳定渗流与水平井筒内变质量湍流耦合的新方法 ,解决了在井筒变质量流体流动模拟过程中井筒边界条件难以确定、地层线性渗流与井筒内非线性湍流难以耦合的问题。同时 ,对不同射孔方式和生产制度下流体水动力学进行了分析 ,研究了射孔入流与水平井筒内流体的相互作用关系及变质量主流体的流动特性。模拟结果表明 ,与圆管湍流相比 ,井筒内变质量流具有更大的压降系数 ,且主流中心速度降低 ,速度剖面呈现内凹形式 ,水平井射孔设计应该利用井筒内流体与渗流的耦合模拟进行优化。     

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.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

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     

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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