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Chinese Journal of Mechanical Engineering 2024年第2期37卷 330-339页

作者： Rui Xiong Zian Zhao Cheng Chen xinggang li Weixiang Shen School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyHawthornVIC 3122Australia

Battery remaining charging time(RCT)prediction can facilitate charging management and alleviate mileage anxiety for electric vehicles(EVs).Also,it is of great significance to improve EV users’***,the RCT for a lithiumion battery pack in EVs changes with temperature and other battery *** study proposes an electrothermal model-based method to accurately predict battery ***,a characteristic battery cell is adopted to represent the battery pack,thus an equivalent circuit model(ECM)of the characteristic battery cell is established to describe the electrical behaviors of a battery ***,an equivalent thermal model(ETM)of the battery pack is developed by considering the influence of ambient temperature,thermal management,and battery connectors in the battery pack to calculate the temperature which is then fed back to the ECM to realize electrothermal ***,the RCT prediction method is proposed based on the electrothermal model and validated in the wide temperature range from-20℃to 45℃.The experimental results show that the prediction error of the RCT in the whole temperature range is less than 1.5%.

关键词： Electric vehicles lithium-ion batteries Remaining charging time Electrothermal model

添加Si和Zn对VW75镁合金显微组织、力学性能和弹性模量的影响

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稀有金属 2024年第6期48卷 796-807页

作者：张驰石国梁张奎李兴刚李永军马鸣龙中国有研科技集团有限公司有色金属材料制备加工国家重点实验室北京100088 有研工程技术研究院有限公司北京101407 北京有色金属研究总院北京100088

Mg-7Gd-5Y-1Nd-0.5Zr (%,质量分数;VW75)是一种获得批量应用的超高强耐热镁合金,但其弹性模量仅约为45 GPa,制约了其减重效果的充分发挥。以提升该合金弹性模量为目的设计了3种成分合金:VW75+1Si, VW75+2Si和VW75+2Si+2Zn(%,质量分数),... 详细信息

Mg-7Gd-5Y-1Nd-0.5Zr (%,质量分数;VW75)是一种获得批量应用的超高强耐热镁合金,但其弹性模量仅约为45 GPa,制约了其减重效果的充分发挥。以提升该合金弹性模量为目的设计了3种成分合金:VW75+1Si, VW75+2Si和VW75+2Si+2Zn(%,质量分数),利用光学显微镜(OM)、扫描电镜(SEM)、 X射线衍射(XRD)等研究了“铸锭→均匀化→挤压”过程的显微组织演变,研究了3种合金在200℃的时效硬化行为,并对挤压态和T5态合金的室温拉伸性能和动态弹性模量进行了测试。结果表明:VW75合金添加Si后在熔体中形成高熔点自生增强相颗粒,增强相存在严重的沉降现象。XRD分析表明增强相为Gd_(5)Si_(3), YSi和Zr_(5)Si_(3),并且多数RE-Si(RE:稀土元素)增强相颗粒同时具有两个成分迥异的区域,即心部的富Y区和外层的富Gd区,暗示熔体降温过程中YSi先形核,Gd_(5)Si_(3)随后以YSi为异质核心析出,添加Zn元素加重了沉降。3种铸态合金中增强相平均粒径位于3.8~5.5μm区间,挤压后被破碎细化至3.4~3.7μm,且分布更加均匀。制备的3种合金中,VW75+2Si+2Zn合金铸态、挤压态和T5态弹性模量最高;挤压态VW75+2Si+2Zn合金具有最大的增强相面积分数(~9.4%)且增强相平均粒径仅~3.5μm,其T5(挤压+人工时效)态弹性模量最高,达到53.4 GPa,但由于RE-Si增强相的出现严重弱化了稀土元素的固溶强化作用,造成抗拉强度和屈服强度大幅降低,同时造成该合金没有时效硬化效应。

关键词：镁合金增强相显微组织力学性能弹性模量

考虑风-光-储不确定性的新型电力系统概率潮流计算

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电测与仪表 2024年第6期61卷 87-93页

作者：曹宏宇梁言贺刘惠颖李琦李兴刚陈月国网黑龙江省电力有限公司营销服务中心哈尔滨150001 黑龙江省电工仪器仪表工程技术研究中心有限公司哈尔滨150001

随着我国“双碳”目标的提出,具有可再生性、环保性和经济性等优点的分布式电源大规模地接入交流配电网以实现电力系统的绿色低碳转型。以风电、光伏为代表的可再生能源出力具有极强的不确定性,同时储能电站的出力呈现出的随机性与波动... 详细信息

随着我国“双碳”目标的提出,具有可再生性、环保性和经济性等优点的分布式电源大规模地接入交流配电网以实现电力系统的绿色低碳转型。以风电、光伏为代表的可再生能源出力具有极强的不确定性,同时储能电站的出力呈现出的随机性与波动性给配电网带来了极大的不确定性,对电力系统的稳定运行提出了挑战。因此文章提出了计及风-光-储不确定性的半不变量概率潮流算法,采用最优带宽核密度估计法建立储能电站输出功率概率模型,同时建立风光电站的概率分布模型。通过去随机化Halton序列对变量进行采样,计算输入变量及输出变量等状态变量的半不变量。最后在改造后的IEEE-33节点测试系统上与蒙特卡洛模拟法进行仿真对比。研究表明,在具有不确定性的新型电力系统中用所提方法计算并分析潮流高效且稳定。

关键词：不确定性储能电站概率潮流半不变量

数字化时代高职院校信息技术基础课程的教学改革研究

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信息与电脑 2024年第15期36卷 228-230页

作者：闫珍珍李幸刚郑州职业技术学院河南郑州450000 平顶山职业技术学院河南平顶山467000

高职院校的信息技术基础课程是学生需要学习的公共基础课程,其目的在于通过对这门课程的学习,提高学生的计算机操作能力,促进数字化创新,为学生的职业发展奠定基础。本文以数字化时代为背景,旨在通过对高职院校信息技术基础课程教学的... 详细信息

高职院校的信息技术基础课程是学生需要学习的公共基础课程,其目的在于通过对这门课程的学习,提高学生的计算机操作能力,促进数字化创新,为学生的职业发展奠定基础。本文以数字化时代为背景,旨在通过对高职院校信息技术基础课程教学的现状进行分析,探讨该课程教学改革的措施,为相关教育工作者提供参考。

关键词：数字化时代高职院校信息技术基础教学改革

Influence of Procedure Parameters on Rheological Property of Semi-Solid AZ91D Magnesium Alloy

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Journal of Rare Earths 2004年第Z2期22卷 47-49页

作者： Jiang Yunxi Xie Shuisheng li xinggang li Lei General Research Institute for Non-Ferrous Metals Beijing 100088China General Research Institute for Non-Ferrous MetalsBeijing 100088China General Research Institute for Non-Ferrous MetalsBeijing 100088China General Research Institute for Non-Ferrous MetalsBeijing 100088China

Semi-solid AZ91D magnesium alloy was investigated in isothermal steady-state condition. The influence of stirring technological parameters such as stirring temperature and shear rate to apparent viscosity of semi-solid alloy slurry was discussed. Apparent viscosity increases with stirring temperature decreases at the same shear rate. At the same stirring temperature, apparent viscosity decreases rapidly at first with shear rate increases, and then apparent viscosity decreases slowly with shear rate increases, when shear rate reaches a certain value, apparent viscosity appears tiny increase. According to the experimental data, the relation between solid volume fraction and apparent viscosity of semi-solid AZ9l D alloy at shear rate 238 s- 1 is fitted by regression method, it supplies useful data to the numerical simulation of semi-solid AZ91D alloy die casting process.

关键词： AZ91D alloy semi-solid rheological property procedure parameter

Phase field simulation of dendrite growth in gas atomized binary Al-Ni droplets

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Particuology 2020年第3期18卷 43-52页

作者： Yuntao Cai Pengjun Fang xinggang li Yi Xu School of Materials Science&Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of Advanced Materials Technology Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China SUSTech Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen 518055China

Catalytic powders with fine microstructures can be produced from a rapidly solidified gas atomized Al-Ni *** solidification microstructure of the droplets is closely linked with heat flow ***,the heat transfer conditions between the gas and droplet are essential to microstructural *** this study,a phase field model for simulating single and multiple dendrite growth in a binary Al-Ni alloy was constructed and the microstructural evolutions occurring during a gas atomization process were *** variations in the heat transfer coefficient and the boundary heat flux were taken into *** results revealed that the heat transfer coefficient of the atomized droplet in flight is correlated with the droplet size and the relative velocity between the droplet and the atomizing *** the simulation,the competition between boundary heat flux extraction and latent heat release from phase transition causes a recalescence process in thermal history,thereby affecting the gradient temperature distribution and,consequently,the dendrite *** growth under the effects of the heat transfer coefficient is restrained continuously because of the decreasing amount of *** computational results confirmed the fine homogeneous microstructure and low microsegregation levels of gas atomized powders.

关键词： Numerical simulation Dendrite morphology Solidification Gas atomization

Modeling and Optimization of Heat Dissipation Structure of EV Battery Pack

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Journal of Beijing Institute of Technology 2018年第1期27卷 29-35页

作者： xinggang li Rui Xiong School of Mechanical Engineering Beijing Institute of Technology

In order to solve the problems of high temperature and inconsistency in the operation of electric vehicle（ EV） battery pack,computational fluid dynamics（ CFD） simulation method is used to simulate and optimize the heat dissipation of battery pack. The heat generation rate at different discharge magnifications is identified by establishing the heat generation model of the battery. In the forced air cooling mode,the Fluent software is used to compare the effects of different inlet and outlet directions,inlet angles,outlet angles,outlet sizes and inlet air speeds on heat dissipation. The simulation results show that the heat dissipation effect of the structure with the inlet and outlet on the same side is better than that on the different sides; the appropriate inlet angle and outlet width can improve the uniformity of temperature field; the increase of the inlet speed can improve the heat dissipation effect significantly. Compared with the steady temperature field of the initial structure,the average temperature after structure optimization is reduced by 4. 8℃ and the temperature difference is reduced by 15. 8℃,so that the battery can work under reasonable temperature and temperature difference.

关键词： electric vehicle(EV) battery pack cooling computational fluid dynamics(CFD) air cooling

框界自然,叙事园庭——中国驻欧洲某馆改造工程中的建构技艺

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建筑技艺（中英文） 2024年第1期30卷 89-93页

作者：易灵洁李兴钢天津大学建筑学院中国建筑设计研究院有限公司胜景几何设计研究中心中国建筑设计研究院有限公司中国建科中国工程院

以“框界自然,叙事园庭”为线索,通过对室外立面遮阳“景窗”和室内公共空间“景墙”的详细记述,呈现中国驻欧洲某馆改造过程中的设计思考和建构技艺。

关键词：框界自然叙事园庭景窗景墙改造更新建构技艺

Microstructural evolution and mechanical properties of Mg-5Y-5Gd-xNd-0.5Zr magnesium alloys at different states

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Rare Metals 2010年第3期29卷 317-322页

作者： li Yongjun ZHANG Kui ZHANG Ya li xinggang MA Minglong State Key Lab for Fabrication and Processing of Nonferrous Metals General Research Institute for Nonferrous Metals Beijing 100088 China Design & Research Institute of Baotou Steel Group Corporation Baotou 014010 China

The microstructural evolution and mechanical properties of Mg-5Y-5Gd-xNd-0.5Zr magnesium alloys at different states were *** results reveal that island compounds at the grain boundaries of the as-cast alloys mainly were Mg24Y5,Mg41Nd5,and Mg5Gd *** homogenization at 808 K for 24 h,the distribution of the island compounds became discrete and Mg5Gd phases mostly decomposed and *** hot extrusion,the grain size was refined to about 20 μm on average,and both the strength and elongation were greatly *** ageing at 523 K for 5 h,the strength of different extruded alloys largely increased but the elongation *** the increase of neodymium content,the strength of the alloys at different states *** content of neodymium element had an obvious effect on the elongation of the designed *** the designed alloys,the Mg-5Y-5Gd-2.2Nd-0.5Zr alloy exhibited the best combination properties and its ultimate tensile strength,yield strength,and elongation could reach 380 MPa,285 MPa,and 9.0%,respectively.

关键词： magnesium alloys neodymium extrusion homogenization microstructural evolution mechanical properties

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瓷器三维建模技术在文物修复中的应用研究

丝网印刷 2024年第19期 113-115页

作者：李幸刚孙琼琼平顶山职业技术学院

聚焦瓷器三维建模技术在文物修复中的应用,旨在探讨利用这项技术提高珍贵瓷器的修复精度,减少物理干预,以及推动文物修复技术的创新。

关键词：瓷器三维建模技术文物修复