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电动车车身骨架静态特性多目标优化

汽车实用技术 2024年第3期49卷 58-63页

作者：张正晴张春梅长安大学汽车学院陕西西安710064

针对微型电动车交通事故频发、车身骨架现有研究不足等问题,根据某款微型电动车车身骨架的有限元模型采取了工程设计中的计算机辅助工程(CAE)分析和多目标优化设计的概念对其车身骨架进行静态特性多目标优化。采取三组方案进行对比,在... 详细信息

针对微型电动车交通事故频发、车身骨架现有研究不足等问题,根据某款微型电动车车身骨架的有限元模型采取了工程设计中的计算机辅助工程(CAE)分析和多目标优化设计的概念对其车身骨架进行静态特性多目标优化。采取三组方案进行对比,在模型精度和计算效率之间做出取舍,得到最优的优化方案,在最终的优化结果对比和计算效率之间,方案三采用移动最小二乘法的方案在精度和效率上最佳。优化后,在车身质量没有大幅度变化的情况下,车身的扭转刚度增加了410.75 N·m/°,弯曲刚度增加了1 041.2 N/mm,该车身骨架静态性能明显提升。

关键词：车身骨架有限元多目标优化静态刚度分析电动车

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金属-有机骨架离子凝胶膜的制备及其在C_(3)H_(6)/C_(3)H_(8)分离中的应用

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膜科学与技术 2024年第2期44卷 19-28页

作者：高云硕孙玉绣刘丽娟耿晨旭张政清乔志华天津工业大学省部共建分离膜与膜过程国家重点实验室化学工程与技术学院天津300387 PPG涂料(天津)有限公司天津300457

通过调节反应时间合成出3种不同颗粒大小金属-有机骨架(ZIF-8),并将其与离子液体1-丙基-3-甲基咪唑双三氟甲磺酰亚胺盐(PmimTf_(2)N)和聚醚共聚酰胺(Pebax 1657)混合制得ZIF-8/IL/Pebax离子凝胶膜,用于对丙烯/丙烷混气体系的分离.通过ZI... 详细信息

通过调节反应时间合成出3种不同颗粒大小金属-有机骨架(ZIF-8),并将其与离子液体1-丙基-3-甲基咪唑双三氟甲磺酰亚胺盐(PmimTf_(2)N)和聚醚共聚酰胺(Pebax 1657)混合制得ZIF-8/IL/Pebax离子凝胶膜,用于对丙烯/丙烷混气体系的分离.通过ZIF-8颗粒与离子液体在Pebax膜中的协同作用,实现了金属-有机骨架(MOF)填料在聚合物基质中高达70%的质量掺杂量,C_(3)H_(6)/C_(3)H_(8)体系的气体分离性能也得到明显提升.研究表明,ZIF-8/IL/Pebax离子凝胶膜相比于Pebax纯膜,C_(3)H_(6)渗透通量提高了385%,达到了227.1 Barrer;同时,C_(3)H_(6)/C_(3)H_(8)的选择性也从3.04提高到了25.11.此外,在不同温度和压力条件下(10~40℃,0.15~0.3 MPa),ZIF-8/IL/Pebax离子凝胶膜均表现出优异的气体分离性能,并表现出了良好的应用前景.

关键词：金属-有机骨架混合基质膜离子凝胶高掺杂量 C_(3)H_(6)/C_(3)H_(8)分离

Predicting of Covalent Organic Frameworks for Membrane-based Isobutene/1,3-Butadiene Separation:Combining Molecular Simulation and Machine Learning

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Chemical Research in Chinese Universities 2022年第2期38卷 421-427页

作者： CAO Xiaohao HE Yanjing zhang zhengqing SUN Yuxiu HAN Qi GUO Yandong ZHONG Chongli State Key Laboratory of Separation Membranes and Membrane Processes Tiangong UniversityTianjin 300387P.R.China School of Material Science and Engineering Tiangong UniversityTianjin 300387P.R.China School of Textile Science and Engineering Tiangong UniversityTianjin 300387P.R.China School of Chemical Engineering and Technology Tiangong UniversityTianjin 300387P.R.China College of Mathematics Science Bohai UniversityJinzhou 121013P.R.China

Efficient separation of C4 olefins is of critical importance and a challenging task in petrochemical industry. Covalent organic frameworks(COFs) could be used as promising candidates for membrane-based isobutene/1,3-butadiene(i-C4H8/C4H6) separation. Owing to large amounts of COFs appearing, however, the rapid prediction of optimal COFs is imperative before experimental efforts. In this work, we combine molecular simulation and machine learning to study COF membranes for efficient isolation of i-C4H8 over C4H6. Using molecular simulation, four potential COF membranes, which possess both high membrane performance score (MPS) value and moderate membrane selectivity were screened out and the mechanism of membrane separation further revealed is an adsorption dominated process. Further, random forest(RF) model with high prediction accuracy(R2>0.84) was obtained and used for elucidating key factors in controlling the membrane selectivity and i-C4H8 permeability. Ultimately, the optimal COF features were obtained through structure-performance relationship study. Our results may trigger experimental efforts to accelerate the design of novel COFs with better i-C4H8/C4H6separation performance.

关键词： Covalent organic framework Isobutene/1 3-butadiene separation Molecular simulation Machine learning

Development and Application of a Power Law Constitutive Model for Eddy Current Dampers

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2403-2419页

作者： Longteng Liang Zhouquan Feng Hongyi zhang zhengqing Chen Changzhao Qian School of Civil Engineering and Architecture Xiamen University of TechnologyXiamen361024China Hunan Provincial Key Laboratory ofWind and Bridge Engineering Hunan UniversityChangsha410082China Fujian Provincial Key Laboratory ofWind Disaster and Engineering Xiamen University of TechnologyXiamen361024China State Key Laboratory of Bridge Engineering Safety and Resilience Hunan UniversityChangsha410082China

Eddy current dampers (ECDs) have emerged as highly desirable solutions for vibration control due to theirexceptional damping performance and durability. However, the existing constitutive models present challenges tothe widespread implementation of ECD technology, and there is limited availability of finite element analysis (FEA)software capable of accurately modeling the behavior of ECDs. This study addresses these issues by developing anewconstitutivemodel that is both easily understandable and user-friendly for FEAsoftware. By utilizing numericalresults obtained from electromagnetic FEA, a novel power law constitutive model is proposed to capture thenonlinear behavior of ECDs. The effectiveness of the power law constitutive model is validated throughmechanicalproperty tests and numerical seismic analysis. Furthermore, a detailed description of the application process ofthe power law constitutive model in ANSYS FEA software is provided. To facilitate the preliminary design ofECDs, an analytical derivation of energy dissipation and parameter optimization for ECDs under harmonicmotionis performed. The results demonstrate that the power law constitutive model serves as a viable alternative forconducting dynamic analysis using FEA and optimizing parameters for ECDs.

关键词： Eddy current damper constitutive model finite element analysis vibration control power law constitutive model

Microscopic defects formation and dynamic mechanical response analysis of Q345 steel plate subjected to explosive load

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Defence Technology（防务技术） 2024年第2期32卷 430-442页

作者： zhengqing Zhou Zechen Du Yulong zhang Guili Yang Ruixiang Wang Yuzhe Liu Peize zhang Yaxin zhang Xiao Wang Research Institute of Macro-Safety Science University of Science and TechnologyBeijing100083China School of Civil and Resource Engineering University of Science and TechnologyBeijing100083China China North Industry Advanced Technology Generalization Institute Beijing100089China College of Field Engineering PLA Army Engineering UniversityNanjing210007China School of Mechanical Engineering Nantong UniversityNantong226019China

As the basic protective element, steel plate had attracted world-wide attention because of frequent threats of explosive loads. This paper reports the relationships between microscopic defects of Q345 steel plate under the explosive load and its macroscopic dynamics simulation. Firstly, the defect characteristics of the steel plate were investigated by stereoscopic microscope(SM) and scanning electron microscope(SEM). At the macroscopic level, the defect was the formation of cave which was concentrated in the range of 0-3.0 cm from the explosion center, while at the microscopic level, the cavity and void formation were the typical damage characteristics. It also explains that the difference in defect morphology at different positions was the combining results of high temperature and high pressure. Secondly, the variation rules of mechanical properties of steel plate under explosive load were studied. The Arbitrary Lagrange-Euler(ALE) algorithm and multi-material fluid-structure coupling method were used to simulate the explosion process of steel plate. The accuracy of the method was verified by comparing the deformation of the simulation results with the experimental results, the pressure and stress at different positions on the surface of the steel plate were obtained. The simulation results indicated that the critical pressure causing the plate defects may be approximately 2.01 GPa. On this basis, it was found that the variation rules of surface pressure and microscopic defect area of the Q345 steel plate were strikingly similar, and the corresponding mathematical relationship between them was established. Compared with Monomolecular growth fitting models(MGFM) and Logistic fitting models(LFM), the relationship can be better expressed by cubic polynomial fitting model(CPFM). This paper illustrated that the explosive defect characteristics of metal plate at the microscopic level can be explored by analyzing its macroscopic dynamic mechanical response.

关键词： Explosive load Q345 steel Micro defect Finite element simulation Dynamic response Data fitting

Pore engineering of ZIF-8 with ionic liquids for membrane-based CO_(2)separation:bearing functional group effect

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Green Chemical Engineering 2021年第1期2卷 104-110页

作者： zhengqing zhang Xuemeng Jia Yuxiu Sun Xiangyu Guo Hongliang Huang Chongli Zhong State Key Laboratory of Separation Membranes and Membrane Processes and School of Chemistry and Chemical Engineering Tiangong UniversityTianjin300387China

CO_(2)separation performance of polymer membranes can be significantly enhanced by selecting porous fillers with high CO_(2)*** liquids incorporation has been recognized as an effective strategy for improving the separation ability of pristine porous ***,the influence of the specific functional groups of ILs in IL@MOF composites on separation performance of MMMs still remains ***,we designed three microenvironment-tuned IL@ZIF-8 composites in which the three ILs contain different functional groups(-CH3,–SO3H,and–NH2).Molecular simulation results showed that the NH2-IL@ZIF-8 has a commendable CO_(2)adsorption capacity and CO_(2)/CH4 adsorptive selectivity,and the results were well confirmed by the following experimental *** importantly,the prepared NH2-IL@ZIF-8 based MMMs also exhibit superior CO_(2)separation performance among the three IL@ZIF-8 based MMMs owning to its high CO_(2)***,this work can provide guidance for designing IL@MOF composites for MMMs fabrication towards gas separation,and the research mode combining molecular simulation prediction and experimental verification can afford valuable reference for material development in membrane separation field.

关键词： Molecular simulation Gas separation Ionic liquids ZIF-8 Mixed-matrix membranes(MMMs)

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超大型湿式冷却塔干湿混合雨区正交优化研究

中国电机工程学报 2022年第22期42卷 8224-8231页

作者：张政清王明勇张德英陈瑞何锁盈高明高效节能及储能技术与装备山东省工程实验室(山东大学能源与动力工程学院) 山东省济南市250061 西安热工研究院有限公司陕西省西安市710054

为研究分流板各参数对干湿雨区冷却塔性能提升效果的影响规律,并得到优化的干湿混合雨区结构参数,该文建立湿式冷却塔三维数值计算模型,并对某超大型湿式冷却塔干湿混合雨区进行正交优化研究。结果表明:对所研究的冷却塔而言,分流板总... 详细信息

为研究分流板各参数对干湿雨区冷却塔性能提升效果的影响规律,并得到优化的干湿混合雨区结构参数,该文建立湿式冷却塔三维数值计算模型,并对某超大型湿式冷却塔干湿混合雨区进行正交优化研究。结果表明:对所研究的冷却塔而言,分流板总覆盖面积为2797.08m2、安装角度为15°、长度为30.9m、安装高度为10.37m、数量4的干湿混合雨区能达到最佳性能提升效果;在该文研究范围内,性能提升效果随分流板总覆盖面积、长度和安装高度的增加而增强,随安装角度的增大先增强后减弱,随分流板数量的增大先减弱后增强;相关性分析表明干区总体积对温降增量的影响要大于干区进口总面积。该研究可为雨区干湿混合冷却模式的工程应用提供理论参考和借鉴。

关键词：超大型湿式冷却塔冷却性能正交优化干湿混合雨区数值计算

以共享性知识生产克服知识贫困——推进实现共同富裕的一种可能路径

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北京航空航天大学学报（社会科学版） 2022年第5期35卷 59-66页

作者：张正清北京航空航天大学马克思主义学院北京100083

共同富裕是社会主义的本质要求,也是中国式现代化的重要特征。而共享性是共同富裕的关键要素,实现共享性有助于实现全体人民的共同富裕。当前,学界对于实现共享性主要从分配入手,很少涉及经济全过程中的共享性,无法有效解决知识贫困问... 详细信息

共同富裕是社会主义的本质要求,也是中国式现代化的重要特征。而共享性是共同富裕的关键要素,实现共享性有助于实现全体人民的共同富裕。当前,学界对于实现共享性主要从分配入手,很少涉及经济全过程中的共享性,无法有效解决知识贫困问题。共享性知识生产强调生产的根本地位,构建了以共享性为核心的知识生态、知识生产方式和知识产品。相对于知识社会主义的知识生产方案,共享性知识可以解决生产的物质性与排他性问题,从而让知识在生产、分配与消费各个环节成为解决知识贫困、促进实现共同富裕的关键要素。

关键词：共同富裕知识生产共享性知识经济知识贫困知识社会主义

一种应用于柔性直流配电系统的具有自动与可控关断功能的直流断路器

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中国电机工程学报 2023年第2期43卷 703-713页

作者：刁晓光李锐蔡久青金翔李鹏张正卿刘飞武汉大学电气与自动化学院湖北省武汉市430072 武汉第二船舶设计研究所湖北省武汉市430010

半导体器件是直流断路器的核心部分。相对于传统的全控型器件(IGBT与MOSFET等),晶闸管由于其低成本、大容量逐渐成为了一种具有前景的直流断路器半导体器件。然而,故障保护的快速性与可靠性对直流断路器的拓扑提出了很高的要求。因此,... 详细信息

半导体器件是直流断路器的核心部分。相对于传统的全控型器件(IGBT与MOSFET等),晶闸管由于其低成本、大容量逐渐成为了一种具有前景的直流断路器半导体器件。然而,故障保护的快速性与可靠性对直流断路器的拓扑提出了很高的要求。因此,该文提出一种具有自动关断(快速)与可控关断(可靠)两种功能的直流断路器。自动关断功能不需要故障检测,通过电路对故障的响应,晶闸管可以被立即关断。可控关断功能可以在断路器内部形成反向电流进而可靠地将晶闸管关断,并且不受到外部电路参数影响。自动关断功能与可控关断功能使用了两个独立的电容,所以这两个功能不会相互影响。最后,通过仿真与2kW的实验验证了所提断路器的功能。

关键词：直流断路器故障保护 T源断路器分布式直流配电网晶闸管