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Journal of Thermal Science 2021年第1期30卷 133-148页

作者： SHAO Wenyang DU Juan YANG Jinguang WANG Xiaofang lyu guochuan School of Energy and Power Engineering Dalian University of TechnologyDalian 116024China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China

The main compressor in a supercritical carbon dioxide(SCO2)Brayton cycle works near the critical point where the physical properties of CO_(2)are far away from the ideal *** investigate the effectiveness of the conventional one-dimensional(1D)loss models for predicting the performance of compressors working in such nontraditional conditions,detailed comparisons of 1D predicted performance,experimental data and threedimensional CFD results are made.A 1D analysis method with enthalpy and total pressure based loss system is developed for multistage SCO2 centrifugal compressors,and it is firstly validated against the experimental results of a single stage SCO2 centrifugal compressor from the Sandia National Laboratory.A good agreement of pressure ratios with experiments can be achieved by the 1D *** the efficiency deviations reveal the potential deficiencies of the parasitic loss *** the basis of the validation,a two-stage SCO2 centrifugal compressor is employed to do the ***-dimensional CFD simulations are *** comparisons are made between the CFD and the 1D results at different stations located in the *** features of the deviations are analyzed in detail,as well as the reasons that might cause these deviations.

关键词： supercritical carbon dioxide Brayton cycle centrifugal compressor one-dimensional performance analysis loss model three-dimensional CFD simulation

Hot Deformation Behavior of Ti-6Al-4V-0.5Ni-0.5Nb Titanium Alloy

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1270-1277页

作者： ZHU guochuan LIU Qiang SONG Shengyin HUI Songxiao YU Yang YE Wenjun QI Jun TANG Zhengwei XU Penghai CNPC Tubular Goods Research Institute Xi’an 710077China State Key Laboratory for Fabrication&Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous MetalsBeijing 100088China China Petroleum Tarim Oilfield Company Korla 841000China

Characterization of hot deformation behavior of Ti-6Al-4V-0.5Ni-0.5Nb titanium alloy was investigated through isothermal compression at various temperatures from 750 to 1050℃and strain rate from 0.01 to 10 s^(-1).The isothermal compression experiment results showed that the peak stress of Ti-6Al-4V-0.5Ni-0.5Nb titanium alloy decreased with the temperature increasing and the strain rate *** softening mechanism was dynamic recovery below T_(β)and changed to dynamic recrystallization above T_(β).The arrheniustype relationship was used to calculate the constitutive equation of Ti-6Al-4V-0.5Ni-0.5Nb alloy in two-phase *** was found that the apparent activation energies were 427.095 kJ·mol^(-1)in theα+βphase region and 205.451 kJ·mol^(-1)in theβphase region,*** the basis of dynamic materials model,the processing map is generated,which shows that the highest peak efficiency of power dissipation of 56%occurs at about 1050℃/0.01 s^(-1).It can be found in the processing maps that the strain had significant effect on the peak region of power dissipation efficiency of Ti-6Al-4V-0.5Ni-0.5Nb ***,optimized hot working regions were investigated and validated through microstructure *** optimum thermo mechanical process condition for hot working of Ti-6Al-4V-0.5Ni-0.5Nb titanium alloy was suggested to be in the temperature range of 950-1000℃with a strain rate of 0.01-0.1 s^(-1).

关键词： titanium alloy hot deformation processing map dynamic recrystallization

Polyzwitterionic cross-linked double network hydrogel electrolyte enabling high-stable Zn anode

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Nano Research 2024年第6期17卷 5278-5287页

作者： Mengyu Shi Junlong Zhang guochuan Tang Ben Wang Sen Wang Xiaoxian Ren Guojie Li Weihua Chen Chuntai Liu Changyu Shen State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentNational Engineering Research Center for Advanced Polymer Processing TechnologyZhengzhou UniversityZhengzhou 450002China College of Chemistry and Green Catalysis Center Zhengzhou UniversityZhengzhou 450001China Research Institute of Interdisciplinary Science and School of Materials Science and Engineering Dongguan University of TechnologyDongguan 523808China

Zn metal anode suffers from dendrite issues and passive byproducts,which severely plagues the practical application of aqueous Zn metal ***,a polyzwitterionic cross-linked double network hydrogel electrolyte composed of physical crosslinking(hyaluronic acid)and chemical crosslinking(synthetic zwitterionic monomer copolymerized with acrylamide)is introduced to overcome these *** the one hand,highly hydrophilic physical network provides an energy dissipation channel to buffer stress and builds a H_(2)O-poor interface to avoid side *** the other hand,the charged groups(sulfonic and imidazolyl)in chemical crosslinking structure build anion/cation transport channels to boost ions’kinetics migration and regulate the typical solvent structure[Zn(H_(2)O)_(6)]^(2+)to R-SO_(3)^(−)[Zn(H_(2)O)_(4)]^(2+),with uniform electric field distribution and significant resistance to dendrites and parasitic *** on the above functions,the symmetric zinc cell exhibits superior cycle stability for more than 420 h at a high current density of 5 mA·cm^(−2),and Zn||MnO_(2)full cell has a reversible specific capacity of 150 mAh·g^(−1)after 1000 cycles at 2 C with this hydrogel ***,the pouch cell delivers impressive flexibility and cyclability for energy-storage applications.

关键词： Zn anode dendrites parasitic reactions polyzwitterion double network hydrogel electrolyte

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上海市沿海地区排水口门工程规模论证

水利水电快报 2024年第10期45卷 68-73页

作者：丁国川上海市水务规划设计研究院(上海市海洋规划设计研究院) 上海200233

为科学开展沿海地区多约束条件下排水口门工程规模论证,以浦东新区北横河及其配套泵闸工程为例,基于平原地区数字河网水动力模型,以水闸最大过闸流量作为关键分析指标,评估排水效益变化趋势。基于固定河道断面和排涝泵站规模,分析24 h... 详细信息

为科学开展沿海地区多约束条件下排水口门工程规模论证,以浦东新区北横河及其配套泵闸工程为例,基于平原地区数字河网水动力模型,以水闸最大过闸流量作为关键分析指标,评估排水效益变化趋势。基于固定河道断面和排涝泵站规模,分析24 h总排水量、代表断面流速等,综合考量社会经济发展需求,结合选址用地条件、对河势和外侧航道的影响以及泵闸工程设计,对不同规模的设计方案进行比选。结果表明:外延伸段河道河口宽150 m、闸净宽72 m、泵站流量80 m3/s为最优河闸泵规模方案。该方案兼顾沿海地理特性、自然环境条件和社会经济需求,可为今后类似工程设计提供参考。

关键词：区域排涝河网水动力模型工程规模沿海地区上海市

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重型运载火箭燃料贮箱FSW核心区温度监测

焊接学报 2024年第9期45卷 30-41页

作者：卢晓红张昊天滕乐隋国川大连理工大学高性能精密制造全国重点实验室大连116024

重型运载火箭燃料贮箱目前通常采用2219-T8高强铝合金,贮箱壁厚高达18 mm,采用搅拌摩擦焊(friction stir welding,FSW)工艺实现筒段纵缝和环缝焊装,FSW核心区极值温度直接影响焊接质量,但由于搅拌头旋转、轴肩遮挡等原因导致FSW核心区... 详细信息

重型运载火箭燃料贮箱目前通常采用2219-T8高强铝合金,贮箱壁厚高达18 mm,采用搅拌摩擦焊(friction stir welding,FSW)工艺实现筒段纵缝和环缝焊装,FSW核心区极值温度直接影响焊接质量,但由于搅拌头旋转、轴肩遮挡等原因导致FSW核心区温度获取困难.文中提出了一种FSW核心区极值温度在位表征方法,首先,基于Deform-3D建立了18 mm厚2219-T8铝合金的FSW温度场仿真模型,实现了18 mm厚2219-T8铝合金平板和环焊温度场表征;然后,基于温度场仿真模型,提取焊件表面特征点温度与核心区极值温度的数据集,采用支持向量回归机算法(support vector regression,SVR)建立FSW核心区极值温度预测模型;最后,红外热像仪实时测得焊件表面特征点温度,结合核心区极值温度预测模型,实现贮箱FSW核心区极值温度监测.试验结果表明,FSW核心区峰值温度监测相对误差<7.22%,核心区最低温度相对误差<9.54%,证实了FSW核心区极值温度监测方法的有效性.

关键词：搅拌摩擦焊核心区温度监测红外热像仪支持向量回归机

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深圳设计竞标与公平性

世界建筑导报 2024年第2期39卷 72-73页

作者：冯果川不详

从上世纪90年代末开始,深圳的建筑设计、城市设计竞赛和投标(下面简称深圳竞标)逐步演变成了深圳建筑生态中最引人注目的现象,在国内和国际上有着相当的影响力和吸引力。这20年来深圳吸引了众多世界和全国的顶尖设计机构前来角逐,一时... 详细信息

从上世纪90年代末开始,深圳的建筑设计、城市设计竞赛和投标(下面简称深圳竞标)逐步演变成了深圳建筑生态中最引人注目的现象,在国内和国际上有着相当的影响力和吸引力。这20年来深圳吸引了众多世界和全国的顶尖设计机构前来角逐,一时间群星璀璨;有机会和顶尖事务所同台竞技或者合作,让深圳的建筑师开阔了眼界,快速提升了设计能力。深圳20年来出现了不少在国内甚至国际上有影响力的设计机构,深圳本地设计力量的竞争力得到了很大的提升。深圳竞标也催生了几家专业的竞标组织机构,他们也开始在别的城市组织投标,把深圳激烈的竞标风格带向了更多的城市。

关键词：设计竞赛竞标建筑设计投标群星璀璨同台竞技公平性竞争力

A cost-effectiveness assessment of the operational parameters of central HVAC systems during pandemics

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Building Simulation 2023年第5期16卷 667-682页

作者： Yufan Chang Zhengtao Ai Jinjun Ye guochuan Ma Department of Building Environment and Energy College of Civil EngineeringHunan UniversityChangshaHunanChina National Center for International Research Collaboration in Building Safety and Environment Hunan UniversityChangshaHunanChina China Southwest Architectural Design and Research Institute ChengduSichuanChina

The present study develops a cost-effectiveness assessment model to analyze the performance of major operational parameters of central HVAC systems in terms of airborne transmission risk,energy consumption,and medical and social cost.A typical multi-zone building model with a central HVAC system is built numerically,and the effect of outdoor air(OA)ratio(from 30%to 100%)and filtration level(MERV 13,MERV 16,and HEPA)are assessed under the conditions of five climate zones in *** with the baseline case with 30%OA and MERV 13 filtration,the airborne transmission risk in zones without infector is negligibly reduced with the increase in OA ratio and the upgrade of filtration level,owing to their slight modification on the equivalent ventilation rate of virus-free ***,depending on climate zone,a 10%increase in OA ratio results in 12.5%-78.6%and 0.1%-8.6%increase in heating and cooling energy consumption,respectively,while an upgrade of filtration level to MERV 16 and HEPA results in an increase of 0.08%-0.2%and 1.4%-2.6%,***,when compared to the use of 100%OA ratio and HEPA filtration,the application of 30%or 40%OA ratio and MERV 13 filtration would save annually an energy and facility related cost of$29.4 billion in China,though giving an increase of approximately$0.1 billion on medical and social cost from the increased number of confirmed *** study provides basic method and information for the formulation of cost-effective operational strategies of HVAC systems coping with the airborne transmission,especially in resource-limited regions.

关键词： outdoor air ratio filtration level airborne transmission risk energy consumption cost-effectiveness

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韧性城市视角下青浦区水利治理体系构建

水利技术监督 2024年第9期 72-75页

作者：丁国川王晓文上海市水务规划设计研究院上海200233 上海市青浦区排水管理所上海201799

上海市青浦区地势低洼,易受“风、暴、潮、洪”威胁,作为太湖流域排洪通道,流域工情水情变化给长三角生态绿色一体化发展示范区建设带来了新压力,目前青浦区面临“因洪致涝”和防洪除涝能力不足等问题。基于韧性城市建设需求,提出青浦... 详细信息

上海市青浦区地势低洼,易受“风、暴、潮、洪”威胁,作为太湖流域排洪通道,流域工情水情变化给长三角生态绿色一体化发展示范区建设带来了新压力,目前青浦区面临“因洪致涝”和防洪除涝能力不足等问题。基于韧性城市建设需求,提出青浦区水利治理体系方案,构建多级洪涝防御体系,加强圩区科学管控,通过打造生态绿心、构建引排通畅的水网空间体系,推动水系统管理能力现代化,为长三角一体化示范区的生态文明建设和经济社会可持续发展提供有力支撑。

关键词：示范区建设绿色生态发展防洪除涝水安全韧性青浦区

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电力工程中配电电缆敷设技术

仪器仪表用户 2024年第2期31卷 25-27页

作者：徐国川张伟王殿玺青岛特锐德电气股份有限公司

配电电缆敷设技术是电力工程中至关重要的一环。本文通过对配电电缆敷设技术的研究，探讨了敷设过程中的关键问题及解决方案。首先，从电缆敷设方式的选择入手，分析了地埋敷设和架空敷设的优缺点，并提出了综合利用两种方式的混合敷设... 详细信息

配电电缆敷设技术是电力工程中至关重要的一环。本文通过对配电电缆敷设技术的研究，探讨了敷设过程中的关键问题及解决方案。首先，从电缆敷设方式的选择入手，分析了地埋敷设和架空敷设的优缺点，并提出了综合利用两种方式的混合敷设方案。其次，针对敷设过程中容易出现的电缆弯曲、拉力过大等问题，提出了相应的解决办法，如采用弹性材料包裹电缆来减少弯曲度，设置张力控制机构来保证拉力在合理范围内。此外，还介绍了一些先进的敷设技术，如无槽道敷设技术和水下敷设技术，它们能有效提高敷设效率，降低工程敷设成本。最后，通过实际案例的分析，验证了所提出的配电电缆敷设技术的可行性和有效性，为电力工程中的配电电缆敷设提供了一定的参考价值。

关键词：配电电缆敷设技术地埋敷设架空敷设混合敷设

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电力工程中的电力负荷预测与调度优化研究

仪器仪表用户 2024年第3期31卷 86-88页

作者：张伟王殿玺徐国川青岛特锐德电气股份有限公司

电力负荷预测和调度优化是电力工程中的重要研究领域，对于确保电力系统的稳定运行具有关键作用。基于此，本文介绍电力负荷预测的基本概念和目标，探讨电力负荷预测的方法，常见负荷预测方法主要包括时间序列分析、回归分析、人工神经... 详细信息

电力负荷预测和调度优化是电力工程中的重要研究领域，对于确保电力系统的稳定运行具有关键作用。基于此，本文介绍电力负荷预测的基本概念和目标，探讨电力负荷预测的方法，常见负荷预测方法主要包括时间序列分析、回归分析、人工神经网络、支持向量机等。这些方法可根据不同数据特点和预测需求，选择合适的模型进行负荷预测。根据实践研究证明，电力负荷预测与调度优化是电力工程中的重要研究内容，通过负荷预测和调度优化，能有效提高电力供应质量，为电力系统可持续发展做出贡献。

关键词：电力负荷预测调度优化电力工程电力系统发电能力