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A Brief Review of High Entropy Alloys and Serration Behavior and Flow Units 被引量:5
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作者 Yong ZHANG Jun-wei QIAO Peter K.LIAW 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2016年第1期2-6,共5页
Multicomponent alloys with high entropy of mixing,e.g.,high entropy alloys(HEAs)and/or multiprincipal-element alloys(MEAs),are attracting increasing attentions,because the materials with novel properties are being... Multicomponent alloys with high entropy of mixing,e.g.,high entropy alloys(HEAs)and/or multiprincipal-element alloys(MEAs),are attracting increasing attentions,because the materials with novel properties are being developed,based on the design strategy of the equiatomic ratio,multicomponent,and high entropy of mixing in their liquid or random solution state.Recently,HEAs with the ultrahigh strength and fracture toughness,excellent magnetic properties,high fatigue,wear and corrosion resistance,great phase stability/high resistance to heat-softening behavior,sluggish diffusion effects,and potential superconductivity,etc.,were developed.The HEAs can even have very high irradiation resistance and may have some self-healing effects,and can potentially be used as the first wall and nuclear fuel cladding materials.Serration behaviors and flow units are powerful methods to understand the plastic deformation or fracture of materials.The methods have been successfully used to study the plasticity of amorphous alloys(also bulk metallic glasses,BMGs).The flow units are proposed as:free volumes,shear transition zones(STZs),tension-transition zones(TTZs),liquid-like regions,soft regions or soft spots,etc.The flow units in the crystalline alloys are usually dislocations,which may interact with the solute atoms,interstitial types,or substitution types.Moreover,the flow units often change with the testing temperatures and loading strain rates,e.g.,at the low temperature and high strain rate,plastic deformation will be carried out by the flow unit of twinning,and at high temperatures,the grain boundary will be the weak area,and play as the flow unit.The serration shapes are related to the types of flow units,and the serration behavior can be analyzed using the power law and modified power law. 展开更多
关键词 high entropy alloy bulk metallic glass serration behavior flow unit
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Permeability prediction using hydraulic flow units and electrofacies analysis 被引量:2
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作者 Amanat Ali Bhatti Atif Ismail +4 位作者 Arshad Raza Raoof Gholami Reza Rezaee Ramasamy Nagarajan Eric Saffou 《Energy Geoscience》 2020年第1期81-91,共11页
It is essential to characterize fluid flow in porous media to have a better understanding of petrophysical properties.Many approaches were developed to determine reservoir permeability among which the integrated analy... It is essential to characterize fluid flow in porous media to have a better understanding of petrophysical properties.Many approaches were developed to determine reservoir permeability among which the integrated analysis of hydraulic flow unit(HFU)and electrofacies(EF)is considered to be useful one.However,the application of HFU and EF analysis has not been totally understood with a limited data to develop correlation for less distance offset wells.In this study,an attempt was made to show the application of integrating HFU and EF for reliable estimation of permeability using core and wireline log data in one of the gas fields in Pakistan.The results obtained indicate that the integrated approach proposed in this study can be used,especially in less distance offset wells when a limited number of data are available for petrophysical characterization. 展开更多
关键词 PERMEABILITY Hydraulic flow units Electrofacies Gas fields Pakistan
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Manipulating internal flow units toward favorable plasticity in Zr-based bulk-metallic glasses by hydrogenation
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作者 Fuyu Dong Yuexin Chu +8 位作者 Mengyuan He Yue Zhang Weidong Li Peter K.Liaw Binbin Wang Liangshun Luo Yanqing Su Robert O.Ritchie Xiaoguang Yuan 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第7期36-45,共10页
This work intends to manipulate the internal flow units in Zr_(55)Cu_(30)Ni_(5)Al_(10)bulk-metallic glasses(BMGs)through plasma-assisted hydrogenation to generate a positive microalloying effect on plasticity.Based on... This work intends to manipulate the internal flow units in Zr_(55)Cu_(30)Ni_(5)Al_(10)bulk-metallic glasses(BMGs)through plasma-assisted hydrogenation to generate a positive microalloying effect on plasticity.Based on the cooperative shear model theory,serration-flow statistics during nanoindentation loading and creep tests during the holding stage were used to analyze the influence of hydrogen on the behavior of flow units in BMGs.Experimental observations showed that the hydrogen in the Zr_(55)Cu_(30)Ni_(5)Al_(10)BMGs caused mechanical softening,plasticity improvement,and structural relaxation.Analysis also showed that the average volume,size,and activation energy of internal flow units in the BMGs all increased as a result of the increase in the hydrogen content.The hydrogenation in the BMGs was found to lead to a prolifera-tion of shear bands,which promoted plasticity.The aggregation of these internal flow units reduced the stress required for plastic deformation through shear bands,ultimately causing softening and structural relaxation. 展开更多
关键词 Bulk-metallic glass Plasma-assisted hydrogenation NANOINDENTATION Internal flow unit Serrations Nano-scale creep
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Vortex Evolution Behavior in Self-Assembly of Flow Units in Metallic Glasses
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作者 Jie Lian Ruyue Song +1 位作者 Yan Chen Lanhong Dai 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2023年第5期603-611,共9页
Shear banding in amorphous metals originates from the activation and percolation of flow units.To uncover the self-assembly dynamics of flow units in metallic glasses,a rectangular sample with two flow units embedded ... Shear banding in amorphous metals originates from the activation and percolation of flow units.To uncover the self-assembly dynamics of flow units in metallic glasses,a rectangular sample with two flow units embedded in the matrix undergoing simple shearing was analyzed using finite element simulations.The vortex evolution behavior,including activation,growth,and collapse during the self-assembly of flow units,was revealed.It was found that the formation of a mature vortex indicates the onset of yielding,and the collapse of the vortex represents the percolation of flow units or shear localization.The effects of initial free volume distribution and the distance between flow units on vortex behavior were also studied.Increasing the initial free volume concentration within flow units or the matrix leads to a gentler vortex evolution process and better homogeneous plasticity.The shape of vortex tends to be"flatter"with the increase in flow units'spacing,and the optimal spacing was found to maximize the strength of the material. 展开更多
关键词 VORTEX Free volume SELF-ASSEMBLY flow units Metallic glasses
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Permeability Prediction Using Hydraulic Flow Units: Baltim North Gas Field, Nile Delta, Egypt
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作者 Abdel Moktader A. El Sayed Samy Zayed Nahla A. El Sayed 《International Journal of Geosciences》 2021年第2期57-76,共20页
168 core samples data of two production wells in the Baltim North field were used to identify the complex discrepancies in reservoir pore geometry which governing the Abu Madi reservoir fluid flow properties. Permeabi... 168 core samples data of two production wells in the Baltim North field were used to identify the complex discrepancies in reservoir pore geometry which governing the Abu Madi reservoir fluid flow properties. Permeability prediction from well logs is significant goal when the core data is rarely available in most cases because<span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> of</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> its expensive cost. The hydraulic flow unit approach was used to classify reservoir rocks according to its pore aperture size in the cored wells. The predicted permeability was calculated from core porosity and core permeability relationship for each flow unit. The difference between Neutron porosity and Density porosity was recognized to distinguish different hydraulic flow units. The higher difference indicates higher quality flow unit and vice versa. For model’s verification the predicted permeability was plotted against the laboratory measured permeability in all studied wells and shows highly matching.</span></span></span> 展开更多
关键词 PERMEABILITY Hydraulic flow units Pore Throat (r35) Baltim Gas Field EGYPT
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Factor Controlling Reservoir Properties and Flow Unit Determination in the Ilam Formation of Dezfol Embayment at Zagros Fold-Thrust Belt, Southwest of Iran
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作者 Peiman Rezaie Akram Jooybari +1 位作者 Majid Mehdi Pour Mansour Gorbani 《Open Journal of Geology》 2016年第7期660-671,共12页
Dezfol embayment in the Southwest of Iran is located in the Zagros fold-thrust belt, which is one of the world’s largest petroleum provinces. Ilam Formation (Santonian-Companian) is one of the reservoir formations in... Dezfol embayment in the Southwest of Iran is located in the Zagros fold-thrust belt, which is one of the world’s largest petroleum provinces. Ilam Formation (Santonian-Companian) is one of the reservoir formations in this area that has been less studied. This paper focused on reservoir properties in this formation using petrography and petrophysics data. According to the petrography studies Ilam Formation composed of limestone as dominant lithology. Detailed petrographic analyses, have led to identification of 10 micro-facies which are represented as a carbonate ramp depositional model. Also petrographic analyses are revealed that cementation, dissolution, compaction and dolomitization are most important digenetic processes. Detailed petrographic analyses and petrophysics data showed that due to mud-supported nature of more facies (inherited low reservoir potential from their depositional settings), diagenetic process plays an important role in increasing of reservoir quality. However cementation and dissolution had negative and positive effects on Ilam reservoir formation, respectively. Finally at the end for better correlation and to create a flow unit, according to the petrography data and using petrophysics log, this reservoir is divided into 5 units (flow unite) by using Geolog software and then they have been correlated across the field. 展开更多
关键词 COMPONENT Diagenetic Process flow unit Petrophysic Reservoir Characterization Ilam Formation Dezfol Embayment
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An Integrated Method of Data Mining and Flow Unit Identification for Typical Low Permeability Reservoir Prediction
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作者 Peng Yu 《World Journal of Engineering and Technology》 2019年第1期122-128,共7页
With the development of oilfield exploration and mining, the research on continental oil and gas reservoirs has been gradually refined, and the exploration target of offshore reservoir has also entered the hot studyst... With the development of oilfield exploration and mining, the research on continental oil and gas reservoirs has been gradually refined, and the exploration target of offshore reservoir has also entered the hot studystage of small sand bodies, small fault blocks, complex structures, low permeability and various heterogeneous geological bodies. Thus, the marine oil and gas development will inevitably enter thecomplicated reservoir stage;meanwhile the corresponding assessment technologies, engineering measures andexploration method should be designed delicately. Studying on hydraulic flow unit of low permeability reservoir of offshore oilfield has practical significance for connectivity degree and remaining oil distribution. An integrated method which contains the data mining and flow unit identification part was used on the flow unit prediction of low permeability reservoir;the predicted results?were compared with mature commercial system results for verifying its application. This strategy is successfully applied to increase the accuracy by choosing the outstanding prediction result. Excellent computing system could provide more accurate geological information for reservoir characterization. 展开更多
关键词 Low PERMEABILITY Reservoir Offshore OILFIELD Hydraulic flow unit flow unit IDENTIFICATION Data Mining
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Classification and Denominationof Flow Units for Clastic Reservoirsof Continental Deposit
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作者 常学军 唐跃刚 +2 位作者 郝建明 张凯 郑家朋 《Journal of China University of Mining and Technology》 2004年第2期209-214,共6页
On the basis of other researchers' achievements and the authors' understanding of flow units, a proposal on classification and denomination of flow units for clastic reservoirs of continental deposit is put fo... On the basis of other researchers' achievements and the authors' understanding of flow units, a proposal on classification and denomination of flow units for clastic reservoirs of continental deposit is put forward according to the practical need of oilfield development and relevant theories. The specific implications of development and geology are given to each type of flow units, which has provided a scientific basis for oil development. 展开更多
关键词 flow units of RESERVOIRS CLASSIFICATION DENOMINATION clastic RESERVOIRS of CONTINENTAL DEPOSIT development and GEOLOGY
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Petrophysical Analysis and Flow Units Characterization for Abu Madi Pay Zones in the Nile Delta Reservoirs
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作者 Abdulaziz M. Abdulaziz Mohamed A. Abouzaid A. S. Dahab 《Open Journal of Geology》 2018年第12期1146-1165,共20页
Field development typically requires detailed petrophysical analysis and well defined hydraulic flow units for comprehensive formation evaluation and reservoir characterization. In the present study, pay zones petroph... Field development typically requires detailed petrophysical analysis and well defined hydraulic flow units for comprehensive formation evaluation and reservoir characterization. In the present study, pay zones petrophysics are studied using an assembly of well log data from 8 wells together with core plugs measurements. Petrophysical analysis showed a good reservoir quality with average water saturation increasing toward the East and Southeast of the study area. Using a multi-linear regression technique on well logs and core data, permeability is estimated at well locations for flow unit characterization and flow capacity calculation. Results showed that five hydraulic flow units are identified through the studied wells, with relatively good correlation. Such correlation indicated a good continuity in the net pay zone of Abu Madi Formation in the Nile Delta reservoirs. The developed hydraulic flow units (HFUs) are classified according to its hydraulic conductivity into two main categories: the first category comprises the units with low permeability (K 1270 mD). The reservoir flow capacity (RFC) of these units indicated the development of 4 distinct classes (~11, ~30, ~80, and greater than 130 D.ft). The wells within the Northwestern part of the study area showed three HFUs that relatively vary from those located at the Southeast where two HFUs are only developed. In addition, the Southeastern part of the reservoir is characterized by good RFC as indicated by the development of high order HFUs (3, 4, and 5) compared to the Northeastern part with predominated low order HFUs (1, 2, and 3). Such results are crucial for the efficient field development and profound reservoir management of oil and gas fields in the Nile Delta. 展开更多
关键词 Abu Madi Formation Evaluation HYDRAULIC flow unitS RESERVOIR CHARACTERIZATION flow Capacity
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Study on Flow Unit of Heavy Oil Bottom Water Reservoir with Over-Limited Thickness in Offshore Oilfield
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作者 Wei Wang Jie Tan +2 位作者 Songru Mu Bo Li Wentong Zhang 《Open Journal of Geology》 2019年第9期507-515,共9页
The upper Ming section of L oilfield is a typical offshore heavy oil bottom-water reservoir with thick fluvial layers. All horizontal wells are developed by natural energy. Due to the few drilling holes and influence ... The upper Ming section of L oilfield is a typical offshore heavy oil bottom-water reservoir with thick fluvial layers. All horizontal wells are developed by natural energy. Due to the few drilling holes and influence by the resolution of seismic data, it is difficult to describe reservoirs with thickness over 20 meters. In this paper, seismic resonance amplitude inversion technology is introduced to restore the real response of thick reservoirs and interbeds by drilling and drilling verification, and the geological bodies with different thickness are displayed by frequency division RGB three primary colors. Flow units of heavy oil reservoirs with bottom water are divided according to the three major factors of interlayer, lithologic internal boundary and water-oil thickness ratio which have the greatest influence on horizontal well development, thick sand bodies are divided into 10 different flow units in three levels, each unit is separated from each other, and the reservoir structure, water-cut characteristics and water-flooding characteristics are different. The reliability of the research is improved by using the dynamic data of horizontal wells and newly drilled passing wells, which provides a basis for tapping the potential of heavy oil reservoirs with bottom water. 展开更多
关键词 Over-Limited THICK Layer INVERSION of Tuned Amplitude Frequency DIVISION RGB Fusion Water-Oil Thickness Ratio flow unit
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Estimation of reservoir and remaining oil prediction based on flow unit analysis 被引量:4
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作者 YIN TaiJu ZHANG ChangMin +2 位作者 ZHANG ShangFeng WANG ShouPing MAO LiHua 《Science China Earth Sciences》 SCIE EI CAS 2009年第S1期120-127,共8页
Through natural partition and clustering analysis,four kinds of flow units were distinguished in Pu53 block,Pucheng Oilfield.Taking the short-term cycle as studying unit,the two-dimensional distribution of each type o... Through natural partition and clustering analysis,four kinds of flow units were distinguished in Pu53 block,Pucheng Oilfield.Taking the short-term cycle as studying unit,the two-dimensional distribution of each type of flow units was forecasted and the short-term cycle was classified into four types based on the two-dimensional characteristics of the flow units.The remaining oil was predicted by conceptual simulation,qualitative analysis and quantitative modeling.The results showed obvious control of the characteristics of reservoir flow units to the remaining oil.E and G units in type I and type II short-term cycles which are distributed continuously in large areas are mostly flooded,while the uncontrolled small isolated G flow unit in type III short-term cycles which were mainly made of F flow unit and F flow unit with continuous distribution become the accumulating place for remaining oil.Thus the development adjustment strategy should optimize the development of small-scale E and G units,strengthen the development of type III short-term cycles,and block out type I short-term cycles.This strategy improves the development of Pu53 block obviously. 展开更多
关键词 flow unit CLASSIFICATION reservoir evaluation reservoir forecast remaining oil development response adjustment project
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Pore size determination using normalized J-function for different hydraulic flow units 被引量:2
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作者 Ali Abedini Farshid Torabi 《Petroleum》 2015年第2期106-111,共6页
Pore size determination of hydrocarbon reservoirs is one of the main challenging areas in reservoir studies.Precise estimation of this parameter leads to enhance the reservoir simulation,process evaluation,and further... Pore size determination of hydrocarbon reservoirs is one of the main challenging areas in reservoir studies.Precise estimation of this parameter leads to enhance the reservoir simulation,process evaluation,and further forecasting of reservoir behavior.Hence,it is of great importance to estimate the pore size of reservoir rocks with an appropriate accuracy.In the present study,a modified J-function was developed and applied to determine the pore radius in one of the hydrocarbon reservoir rocks located in the Middle East.The capillary pressure data vs.water saturation(PceSw)as well as routine reservoir core analysis include porosity(4)and permeability(k)were used to develop the J-function.First,the normalized porosity(4z),the rock quality index(RQI),and the flow zone indicator(FZI)concepts were used to categorize all data into discrete hydraulic flow units(HFU)containing unique pore geometry and bedding characteristics.Thereafter,the modified J-function was used to normalize all capillary pressure curves corresponding to each of predetermined HFU.The results showed that the reservoir rock was classified into five separate rock types with the definite HFU and reservoir pore geometry.Eventually,the pore radius for each of these HFUs was determined using a developed equation obtained by normalized J-function corresponding to each HFU.The proposed equation is a function of reservoir rock characteristics including 4z,FZI,lithology index(J*),and pore size distribution index(3).This methodology used,the reservoir under study was classified into five discrete HFU with unique equations for permeability,normalized J-function and pore size.The proposed technique is able to apply on any reservoir to determine the pore size of the reservoir rock,specially the one with high range of heterogeneity in the reservoir rock properties. 展开更多
关键词 Pore size Pore geometry Hydraulic flow unit Capillary pressure J-function
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渐进式优化框架下的地质灾害易发性评价与可解释性分析
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作者 刘洋 刘庆丽 +2 位作者 吴益平 江君 殷坤龙 《安全与环境工程》 北大核心 2026年第1期1-18,共18页
为构建乡镇尺度的泥石流易发性精细化建模框架,聚焦位于中国西南亚热带季风气候区的复杂山区,提出了一种基于遗传算法(genetic algorithm,GA)-分类提升(categorical boosting,CatBoost)-沙普利加法解释(Shapley additive explanations,S... 为构建乡镇尺度的泥石流易发性精细化建模框架,聚焦位于中国西南亚热带季风气候区的复杂山区,提出了一种基于遗传算法(genetic algorithm,GA)-分类提升(categorical boosting,CatBoost)-沙普利加法解释(Shapley additive explanations,SHAP)的渐进式优化框架。该框架整合了最优流域单元选择、高质量负样本集构建和超参数优化策略。首先,在前处理部分,构建了泥石流影响因素数据库,设计了5种不同汇流累积量阈值的流域单元,并优化了负样本采样策略;随后,在模型构建阶段,采用极端梯度提升(extreme gradient boosting,XGBoost)、轻量梯度提升机(light gradient boosting machine,LGBM)、CatBoost和自然梯度提升(natural gradient boosting,NGBoost)算法作为基础模型,并集成GA超参数优化方法进行最优测试;最后,采用SHAP方法对泥石流影响因素的贡献度进行了量化分析,揭示了西南山区泥石流发生的主要驱动因素。结果表明:汇流累积量阈值为1000的流域单元表现最佳;CatBoost模型的性能优于其他算法;通过超参数优化后,GA-CatBoost模型的预测性能达到最高,其准确度、F1值和曲线下面积(area under the curve,AUC)分别为0.860、0.880和0.910;SHAP分析显示,岩性、土壤类型和归一化差分植被指数(normalized difference vegetation index,NDVI)是研究区内泥石流发生的最主要影响因素。研究结果可为乡镇级泥石流的风险评估及管理与防控工作提供技术支持和决策参考。 展开更多
关键词 泥石流易发性 流域单元 乡镇尺度 梯度提升算法 超参数优化
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致密油藏开发前后流动单元动态变化与剩余油分布关系
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作者 尹虎 屈红军 +4 位作者 张磊岗 孙晓晗 朱荣幸 杨晓锋 苏帅 《西北大学学报(自然科学版)》 北大核心 2026年第1期171-186,共16页
以鄂尔多斯盆地长8致密油藏为例,利用聚类分析方法,根据有效厚度、孔隙度、渗透率、储层品质因子和含油饱和度5个参数划分出4类原始流动单元,在静态参数的基础上,根据储层加砂强度、产液量2个动态参数将研究区储层划分为4类开发后流动单... 以鄂尔多斯盆地长8致密油藏为例,利用聚类分析方法,根据有效厚度、孔隙度、渗透率、储层品质因子和含油饱和度5个参数划分出4类原始流动单元,在静态参数的基础上,根据储层加砂强度、产液量2个动态参数将研究区储层划分为4类开发后流动单元,并对开发前后流动单元进行三维建模,对流动单元的分布特征进行分析;结合剩余油数值模拟研究,对研究区油藏进行挖潜级别划分并给出了开发策略。研究表明,沉积相展布控制着原始流动单元分布,高级别流动单元沿着主河道分布延伸,砂体厚度大,砂体呈叠加式连续展布;低级别流动单元分布于主河道两侧,砂体厚度变小,砂体呈分离式。开发方式控制着动态流动单元,经压裂改造后,井周流动单元普遍优于井间流动单元。油藏经过压裂改造及阶段开采后,流动单元A类和B类区由于流动性强、采出程度高导致含油饱和度逐渐降低,剩余油富集区逐渐向流动性相对较差的C类和D类流动单元转移。根据开发后流动单元分布和剩余油展布特征,可将开发区块划分为6种挖潜级别,一级挖潜区剩余油含量和开发后流动单元级别均高,为下一步生产开发的首选区域;二级挖潜区开发后流动单元级别较低,但剩余油多,可配合一级挖潜储层进行共同开发。本研究可为同类型的致密油藏流动单元研究和后期开发方案调整提供借鉴意义。 展开更多
关键词 鄂尔多斯盆地 长8油层组 致密油藏 流动单元 剩余油分布
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基于鱼类栖息需求的生态流量过程研究
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作者 周正 于子铖 +6 位作者 任志雄 丁洋 王少飞 刘哲 李书芳 张景洲 任冲 《水利水电技术(中英文)》 北大核心 2026年第1期118-130,共13页
【目的】为有效解决河流栖息地结构受损、功能退化这一现实问题,【方法】以滹沱河流域灵寿段为研究区,基于现场踏勘、生态监测、文献调研、数值模拟等手段,引入水力单元概念,科学筛选目标鱼类,梳理归纳其水文-地貌栖息需求,定量研判水... 【目的】为有效解决河流栖息地结构受损、功能退化这一现实问题,【方法】以滹沱河流域灵寿段为研究区,基于现场踏勘、生态监测、文献调研、数值模拟等手段,引入水力单元概念,科学筛选目标鱼类,梳理归纳其水文-地貌栖息需求,定量研判水文变化下不同鱼类关键阶段的栖息地空间分布。【结果】结果表明:不同流量变化下水力单元空间分布差距明显,水力单元多样性指数在200 m^(3)/s时取得最大值,当流量为120 m^(3)/s时,深潭区域面积最大为796956 m^(2),当流量为240 m^(3)/s时,急流区域面积最大为1005619 m^(2),以4种目标鱼类栖息需求为导向明确了研究区生态流量过程,在5—6月鱼类产卵集中期生态流量可达200~240 m^(3)/s,越冬期间为80~120 m^(3)/s,索饵期可达120~200 m^(3)/s。【结论】通过对水力单元时空分布的量化分析,统筹考虑关键物种不同生命周期的需求,分期动态确定了受损河流生态流量过程,从而为区域河湖生态复苏提供理论支撑。 展开更多
关键词 鱼类栖息地 不同生命周期 数值模拟 生态流量 水力单元 滹沱河 环境DNA
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黏性泥石流对公路桥墩冲击力影响因素研究
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作者 刘志锋 刘建鑫 +2 位作者 林志红 张静 陈欢欢 《路基工程》 2026年第1期230-234,共5页
通过改变粗颗粒、红土、沙、水的含量,配制不同容重的黏性泥石流进行模型试验,研究其对桥墩的冲击作用。结果表明:泥石流冲击力随着水槽坡度的增大而增大,低坡度时流速对冲击力的影响较大,高坡度时容重对冲击力的影响较大,泥石流容重和... 通过改变粗颗粒、红土、沙、水的含量,配制不同容重的黏性泥石流进行模型试验,研究其对桥墩的冲击作用。结果表明:泥石流冲击力随着水槽坡度的增大而增大,低坡度时流速对冲击力的影响较大,高坡度时容重对冲击力的影响较大,泥石流容重和流速对冲击力的影响转换临界坡度约18°;相同条件下黏土含量越高,泥石流冲击力越小;泥石流流速与冲击力为开口向下的二次函数关系,泥石流泥深与冲击力为开口向上的二次函数关系。 展开更多
关键词 公路工程 黏性泥石流 冲击力 容重 流速 泥深 黏土含量
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Implementation of a Petrographical and Petrophysical Workflow Protocol for Studying the Impact of Heterogeneity on the Rock Typing and Reservoir Quality of Reefal Limestone:A Case Study on the Nullipore Carbonates in the Gulf of Suez
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作者 Mona G.SAFA Bassem S.NABAWY +2 位作者 Ahmed M.K.BASAL Mohammad A.OMRAN Aref LASHIN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第5期1746-1762,共17页
This study focuses on the heterogeneity of the middle Miocene syn-rift Belayim nullipore(reefal)marine sequences in the Gulf of Suez and its impacts on reservoir quality.The sequences consist of coralline algal reef l... This study focuses on the heterogeneity of the middle Miocene syn-rift Belayim nullipore(reefal)marine sequences in the Gulf of Suez and its impacts on reservoir quality.The sequences consist of coralline algal reef limestones with a highly complex dual-porosity system of primary and secondary porosities of widely varying percentages.To achieve a precise mathematical modeling of these reservoir sequences,a workflow protocol was applied to separate these sequences into a number of hydraulic flow units(HFUs)and reservoir rock types(RRTs).This has been achieved by conducting a conventional core analysis on the nullipore marine sequence.To illustrate the heterogeneity of the nullipore reservoir,the Dykstra-Parsons coefficient(V)has been estimated(V=0.91),indicating an extremely heterogeneous reservoir.A slight to high anisotropy(λ_(k))has been assigned for the studied nullipore sequences.A stratigraphic modified Lorenz plot(SMLP)was applied to define the optimum number of HFUs and barriers/baffles in each of the studied wells.Integrating the permeability-porosity,reservoir quality index-normalized porosity index(RQI-NPI)and the RQI-flow zone indicator(RQIFZI)plots,the discrete rock types(DRT)and the R35 techniques enable the discrimination of the reservoir sequences into 4 RRTs/HFUs.The RRT4 packstone samples are characterized by the best reservoir properties(moderate permeability anisotropy,with a good-to-fair reservoir quality index),whereas the RRT1 mudstone samples have the lowest flow and storage capacities,as well as the tightest reservoir quality. 展开更多
关键词 reservoir heterogeneity nullipore rock typing hydraulic flow units Dykstra-Parsons coefficient stratigraphic modified Lorenz plot(SMLP)
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基于改进K均值聚类分析和粒子群算法的阀门流量特性曲线优化
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作者 任鹏伟 肖宇翔 +3 位作者 孙嘉明 高源 文思源 何成兵 《汽轮机技术》 北大核心 2026年第1期69-75,共7页
针对火电机组阀门流量特性实际曲线偏离理论曲线的问题,提出一种基于改进K均值聚类分析和改进粒子群算法相结合的阀门流量特性曲线优化方法。首先,采用数据加和筛选法进行历史运行数据预处理,建立原始阀门流量特性数据集;然后,基于等效... 针对火电机组阀门流量特性实际曲线偏离理论曲线的问题,提出一种基于改进K均值聚类分析和改进粒子群算法相结合的阀门流量特性曲线优化方法。首先,采用数据加和筛选法进行历史运行数据预处理,建立原始阀门流量特性数据集;然后,基于等效蒸汽流量法建立阀门流量特性优化数据集;之后,提出改进K均值聚类分析算法拟合构建实际阀门流量特性曲线;最后,提出改进粒子群算法获得优化后的阀门流量特性曲线。以经典测试函数为例,验证了改进粒子群算法可有效避免进行复杂优化时易陷入局部最优的问题,并具有很高的参数识别精度和鲁棒性。以某330MW机组为例,详细分析了阀门流量特性曲线优化过程,基于该机组的一次调频仿真模型,比较了阀门优化前后一次调频性能,验证了本文方法的有效性。 展开更多
关键词 火电机组 阀门流量特性曲线 数据加和筛选法 改进K均值聚类分析 改进粒子群算法
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水系有机液流电池储能辅助火电机组AGC调频技术的可行性研究
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作者 许霖帆 兀鹏越 +7 位作者 郑昀 王烽 王晶 康祯 郭昊 林怡玢 刘旭华 李志鹏 《热力发电》 北大核心 2026年第2期86-94,共9页
【目的】为适应高比例新能源并网对电网频率稳定性的紧迫要求,解决火电机组调频响应速度慢的问题,水系有机液流电池凭借其循环寿命长和自放电率低等优点,成为适合调频场景的技术选择。【方法】介绍了一种以水系有机液流电池作储能的火... 【目的】为适应高比例新能源并网对电网频率稳定性的紧迫要求,解决火电机组调频响应速度慢的问题,水系有机液流电池凭借其循环寿命长和自放电率低等优点,成为适合调频场景的技术选择。【方法】介绍了一种以水系有机液流电池作储能的火储联合AGC调频技术,论述了火储协同技术和水系有机液流电池的基本原理,测试了液流电池的核心性能参数,提出了液流电池辅助火电机组的调频控制策略,并将其应用于罗源电厂200 kW/400 kW·h火储联合调频示范工程项目。【结果】实际运行情况和分析测试结果表明,水系有机液流电池具备快速调节和精确输出的响应特性,可增强联合系统的调频能力。【结论】将水系有机液流电池应用于火电调频具有可行性。 展开更多
关键词 水系有机液流电池 储能 火电机组 AGC调频 功率响应
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330 MW火电机组汽轮机阀门流量特性分析与优化
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作者 赵尚羽 杜之正 +1 位作者 邱树良 宋瑞福 《东北电力技术》 2026年第2期44-48,共5页
针对某330 MW火电机组汽轮机开展阀门流量特性分析优化研究,基于锅炉定压运行数据和特定参数,绘制阀门实际流量特性曲线与理想流量特性曲线,通过计算和对比发现二者存在较大非线性度。运用手动修正的方法优化阀门流量函数,使实际流量特... 针对某330 MW火电机组汽轮机开展阀门流量特性分析优化研究,基于锅炉定压运行数据和特定参数,绘制阀门实际流量特性曲线与理想流量特性曲线,通过计算和对比发现二者存在较大非线性度。运用手动修正的方法优化阀门流量函数,使实际流量特性曲线趋于理想状态。试验结果表明,机组修正后的阀门流量函数下的实际流量曲线与理想流量曲线更加吻合,其非线性度小于2%。因此,机组一次调频和AGC的质量得到有效提升,在安全运行的基础上取得了更高的经济效益。 展开更多
关键词 火电机组 汽轮机 阀门流量特性 顺阀控制 等效流量
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