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基于涡分析的旋涡泵内流动能量转换特性研究

农业机械学报 2024年第5期55卷 167-175页

作者：杨伟峰张人会杨鸿德陈学炳兰州理工大学能源与动力工程学院兰州730050 兰州理工大学甘肃省流体机械及系统重点实验室兰州730050

为研究旋涡泵内复杂的旋涡特征,量化泵内旋涡体积和强度,分析旋涡结构对能量转换和能量损失的影响规律,采用非定常数值模拟和外特性实验相结合的方法对单级旋涡泵进行分析,综合使用Ω方法和Liutex方法对泵内旋涡进行识别和强度表征,提... 详细信息

为研究旋涡泵内复杂的旋涡特征,量化泵内旋涡体积和强度,分析旋涡结构对能量转换和能量损失的影响规律,采用非定常数值模拟和外特性实验相结合的方法对单级旋涡泵进行分析,综合使用Ω方法和Liutex方法对泵内旋涡进行识别和强度表征,提出平均旋涡强度进行量化研究,并结合动能方程的涡动力学分解式以及涡量分解理论进行分析。结果表明:泵内的旋涡充分发展区域存在螺旋形的管状旋涡结构,该旋涡从叶轮流道流出进入侧流道,并且随着流量的增大,涡管数量减少且旋涡强度降低;流量的增大使得叶轮内的旋涡体积和强度减小,而其在侧流道内相对变化较小,相同工况时叶轮内的平均旋涡强度远大于侧流道内;压力梯度对流体动能转换的贡献最大,旋涡结构引起的动量输运和耗散损失占比较小,但刚性涡量即旋涡结构的强度与动量输运呈正相关,变形涡量则与拟涡能损失相关性较强。

关键词：旋涡泵旋涡 Ω方法 Liutex方法拟涡能

Characteristics, formation and evolution of pre-salt dolomite reservoirs in the fifth member of the Ordovician Majiagou Formation, mid-east Ordos Basin, NW China

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Petroleum Exploration and Development 2019年第6期46卷 1153-1164页

作者： FU Siyi ZHANG chenggong chen hongde chen Anqing ZHAO Junxing SU Zhongtang YANG Shuai WANG Guo MI Wentian State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China School of Mines Inner Mongolia University of TechnologyHohhot 010051China

The characteristics and formation of the pre-salt dolomite reservoirs in the fifth member of Ordovician Majiagou Formation in the mid-east Ordos Basin are investigated through observation of cores and thin sections,and geochemical analysis.(1)The pre-salt dolomites can be divided into dolomicrite,grain dolomite and dolarenite,in which the main reservoir space consists of intercrystalline pores and various dissolved pores.(2)The diagenesis in the study area is complex and mainly includes dolomitization,dissolution,filling,and recrystallization.(3)Multi-stages of dolomitization,including penecontemporaneous capillary concentration dolomitization,seepagereflux dolomitization during penecontemporaneous and shallow burial stage,and burial dolomitization in later stage,are conducive to the preservation of primary pores and development of secondary pores.(4)Multi-stages of dissolution also have strong influence on the development of secondary pores;the secondary transgression and regression cycles during the contemporaneous-penecontemporaneous stage led to exposure and dissolution of soluble minerals and thus the generation of secondary pores.(5)In the burial stage,reservoir pores were further improved due to organic acid dissolution and the dissolution by hydrosulphuric acid from thermochemical sulfate reduction(TSR)and its product H2S.(6)High H2S concentration area in pre-salt reservoirs can thus be considered as targets for future exploration.

关键词： Ordos Basin Ordovician Majiagou Formation dolomite evaporites dolomitization dissolution

渤海湾盆地辽东湾地区辽西凸起中北段太古宇潜山成储规律及主控因素

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石油实验地质 2024年第1期46卷 46-53页

作者：郭龙龙王峻张春光陈洪德成都理工大学沉积地质研究院成都610059 中海石油(中国)有限公司天津分公司天津300452

渤海湾盆地是我国潜山油气资源勘探的重点地区之一,为了打开该区太古宇潜山勘探新局面,对辽东湾地区太古宇潜山成储规律及主控因素进行了研究。基于薄片、测井、地震等钻井资料,分析了辽西凸起中北段太古宇潜山岩石学特征、岩石展布特... 详细信息

渤海湾盆地是我国潜山油气资源勘探的重点地区之一,为了打开该区太古宇潜山勘探新局面,对辽东湾地区太古宇潜山成储规律及主控因素进行了研究。基于薄片、测井、地震等钻井资料,分析了辽西凸起中北段太古宇潜山岩石学特征、岩石展布特征、储层特征、构造演化和裂缝特征。研究表明,辽东湾地区辽西凸起太古宇潜山由片麻岩类、变质花岗岩类和碎裂岩类等组成,并以片麻岩为主;现今构造呈南高北低特征,北部地层保存相对完好,南部地层上部具剥蚀迹象,岩浆岩比例自北向南逐渐增高。该区太古宇变质岩以裂缝型储层为主,岩石中暗色矿物含量与岩石脆性呈反比关系;构造变形导致裂缝发育,太古宇潜山发育三组构造裂缝,即燕山早期受到NE向强剪切和SN向强挤压的应力方向发育NNE向剪裂缝和SN向张裂缝,喜马拉雅早期受到NW向强伸展和NE向弱剪切的应力方向发育NE向剪裂缝和北东向张裂缝,喜马拉雅晚期受到NE向强剪切和NW向弱伸展的应力方向发育EW向张裂缝及NE向和NW向共轭剪裂缝,区域构造差异活动程度控制了裂缝的有效性;燕山运动是变质岩储层主要造缝期,喜马拉雅期裂缝以方解石充填、半充填为主,后期经溶蚀可构成有效裂缝。

关键词：主控因素储层潜山太古宇辽西凸起渤海湾盆地

e抗原阴性慢性HBV感染者非活动期与不确定期的评估及治疗

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胃肠病学和肝病学杂志 2024年第3期33卷 336-341页

作者：蔡欣奕陈洪德成都市公共卫生临床医疗中心结核科四川成都610000

e抗原阴性慢性乙型肝炎病毒(hepatitis B virus,HBV)感染是世界范围内慢性乙型肝炎(chronic hepatitis B,CHB)的主要形式,其管理是世界公共卫生的重大负担。近年,对慢性HBV感染的进一步探索,使得CHB的管理更加精确。欧洲肝病学会提出将... 详细信息

e抗原阴性慢性乙型肝炎病毒(hepatitis B virus,HBV)感染是世界范围内慢性乙型肝炎(chronic hepatitis B,CHB)的主要形式,其管理是世界公共卫生的重大负担。近年,对慢性HBV感染的进一步探索,使得CHB的管理更加精确。欧洲肝病学会提出将CHB自然史分为以下5个阶段:HBeAg阳性HBV感染、HBeAg阳性慢性肝炎、HBeAg阴性HBV感染、HBeAg阴性慢性肝炎、HBeAg阴性HBV感染(隐匿性HBV感染),有相当比例的患者不属于以上任何一个分期,即不确定期。本文总结了关于e抗原阴性HBV感染的文献和指南,旨在帮助临床医师使用无创性工具(如乙肝表面抗原定量和弹性成像)评估HBeAg阴性非活动期与不确定期患者,并及时开始抗病毒治疗。

关键词： e抗原阴性HBV感染自然史非活动期不确定期抗病毒治疗

基于响应面法的换流变压器励磁涌流峰值快速计算分析

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科技和产业 2024年第5期24卷 227-232页

作者：吴永恒许尧彭明智胡永波袁洪德陈志伟国网安徽省电力有限公司超高压分公司合肥230022 合肥工业大学电气与自动化工程学院合肥230009

为解决传统数值法和软件仿真法求解变压器励磁涌流存在模型参数固定、效率低下等问题,提出将响应面拟合计算方法运用在换流变励磁涌流的计算中,实现考虑到主心柱在不同剩磁的条件下的励磁涌流峰值随合闸角变化的高效计算分析。理论分析... 详细信息

为解决传统数值法和软件仿真法求解变压器励磁涌流存在模型参数固定、效率低下等问题,提出将响应面拟合计算方法运用在换流变励磁涌流的计算中,实现考虑到主心柱在不同剩磁的条件下的励磁涌流峰值随合闸角变化的高效计算分析。理论分析变压器励磁涌流的产生机理,提取出关键影响因素,采用参数建模建立换流变压器模型,通过响应面试验设计拟合绕组初始电流、合闸角和励磁涌流峰值之间的响应面模型,并验证响应面的精度。研究成果可为变压器励磁涌流快速计算分析、电力变压器数字孪生技术提供技术参考。

关键词：换流变压器励磁涌流响应面法快速计算

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飞机线路系统故障电弧检测技术综述

舰船电子工程 2024年第4期44卷 1-5页

作者：张志亮戴洪德王希彬贾临生陈美男海军航空大学航空基础学院烟台264001 中国人民解放军32151部队邢台054000

故障电弧容易引发飞机电气火灾事故,很难在地面上复现并检测,电气线路系统检修需要耗费大量的人力物力来完成。针对故障电弧不易检测的难题,论文对飞机故障电弧检测技术进行归纳总结,将故障电弧检测方法归纳为数学模型、物理特性和电气... 详细信息

故障电弧容易引发飞机电气火灾事故,很难在地面上复现并检测,电气线路系统检修需要耗费大量的人力物力来完成。针对故障电弧不易检测的难题,论文对飞机故障电弧检测技术进行归纳总结,将故障电弧检测方法归纳为数学模型、物理特性和电气方法,其中电气方法又分为时域法、频域法、时频域法,分析了各种方法的优缺点,并展望了故障电弧检测技术未来的研究方向。

关键词：故障电弧电弧模型小波分析波动率

A Free Surface Frequency Domain Green Function with Viscous Dissipation and Partial Reflections from Side Walls

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Journal of Marine Science and Application 2011年第3期10卷 259-264页

作者： hongde Qin Jing Shen Xiaobo chen College of Shipbuilding Engineering Harbin Engineering University Harbin 150001 China Research Department Bureau Veritas 925 70 Neuilly-Sur-Seine France

The free-surface Green function method is widely used in solving the radiation or diffraction problems caused by a ship or ocean structure oscillating on the waves. In the context of inviscid potential flow, hydrodynamic problems such as multi-body interaction and tank side wall effect cannot be properly dealt with based on the traditional free-surface frequency domain Green function method, in which the water viscosity is omitted and the energy dissipation effect is absent. In this paper, an open-sea Green function with viscous dissipation was presented within the theory of visco-potential flow. Then the tank Green function with a partial reflection from the side walls in wave tanks was formulated as a formal sum of open-sea Green functions representing the infinite images between two parallel side walls of the source in the tank. The new far-field characteristics of the tank Green function is vitally important for improving the validity of side-wall effects evaluation, which can be used in supervising the tank model tests.

关键词：格林函数方法自由表面能量耗散反射波侧墙频域黏性格林函数理论

A new approach to the prediction of transmembrane structures

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Chinese Science Bulletin 2008年第7期53卷 1011-1014页

作者： LIU hongde WANG Rui LU XiaoQuan chen Jing LIU XiuHui DING Lan College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 China College of Life Science Northwest Normal University Lanzhou 730070 China

About 20%-30% of genome products have been predicted as membrane proteins, which have sig-nificant biological functions. The prediction of the amount and position for the transmembrane protein helical segments (TMHs) is the hot spot in bioinformatics. In this paper, a new approach, maximum spectrum of continuous wavelet transform (MSCWT), is proposed to predict TMHs. The predictions for eight SARS-CoV membrane proteins indicate that MSCWT has the same capacity with software TMpred. Moreover, the test on a dataset of 131 structure-known proteins with 548 TMHs shows that the predic-tion accuracy of MSCWT for TMHs is 91.6% and that for membrane protein is 89.3%.

关键词：横跨膜构造 TMHs 光谱学子波转移

Geological Features of Devonian Sedimentary Basins in South China and Their Deposition and Mineralization

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Acta Geologica Sinica(English Edition) 1994年第1期68卷 57-69,109-110页

作者： Liu Wenjun, Zhang Jinquan and chen hongde chengdu College of Geology, chengdu, Sichuan chengdu College of Geology Chengdu Sichuan

The Devonian succession in South China is well-known for its complete development, vari-fied sedimentary types, remarkable lithofacies variation and abundant mineral resources. The South China plate was formed by the collision and collage of the Yangtze plate and the Cathaysian plate. The collision began approximately at the Jinningian stage and the collage was not finalized until the Guangxian movement. It was on the South China plate with a somewhat different nature of the basement that the Devonian deposition formed.

关键词： Devonian features of sedimentary basins mineralization South China