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基于MATLAB的可重用动态仿真模型库的设计与实现

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系统仿真学报 2004年第7期16卷 1450-1452,1480页

作者：刘兴刚袁枫华徐心和郝丽娜薛定宇东北大学信息科学与工程学院东北大学机械工程与自动化学院

结合研究冷连轧过程控制力能参数模型的需要,提出了开发冷连轧动态仿真模型库系统的设想。为此设计了仿真模型库系统的功能结构和面向对象的系统层次结构体系。采用MATLAB仿真平台,运用软件可重用技术,构造了冷连轧仿真领域模型库。利用... 详细信息

结合研究冷连轧过程控制力能参数模型的需要,提出了开发冷连轧动态仿真模型库系统的设想。为此设计了仿真模型库系统的功能结构和面向对象的系统层次结构体系。采用MATLAB仿真平台,运用软件可重用技术,构造了冷连轧仿真领域模型库。利用MATLAB提供的动态数据交换DDE功能,用M语言编写的S函数块,实现了仿真模型库和现场监控平台之间的动态数据交换。应用实例表明本文提出的冷连轧动态仿真模型库系统具有较好的实用价值。

关键词：仿真模型库可重用技术 DDE 冷连轧

各向异性Kelvin泡沫胞元高径比对其流动传热特性的影响

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空气动力学学报 2024年第1期42卷 55-66,I0002页

作者：张超孔祥壮杜雁霞王娴肖光明西安交通大学航天航空学院机械结构强度与振动国家重点实验室陕西省先进飞行器服役环境与控制重点实验室西安710049 空天飞行空气动力科学技术全国重点实验室绵阳621000

飞行器热管理系统中所用的高孔隙率泡沫材料具有质量轻、比表面积大等优点,孔隙尺度几何参数的优化设计对有效提升综合传热性能、降低结构质量至关重要。以各向异性Kelvin泡沫胞元为研究对象,采用混合热格子Boltzmann方法以及多GPU加速... 详细信息

飞行器热管理系统中所用的高孔隙率泡沫材料具有质量轻、比表面积大等优点,孔隙尺度几何参数的优化设计对有效提升综合传热性能、降低结构质量至关重要。以各向异性Kelvin泡沫胞元为研究对象,采用混合热格子Boltzmann方法以及多GPU加速技术,实现了同时考虑泡沫骨架导热和多胞元孔隙尺度强迫对流换热的共轭传热数值模拟。在上述基础上,分别选取了Re=10、100、1000计算条件,开展了不同胞元高径比(H/D=0.5、0.75、1.0、1.5、2.0)对其流动传热特性的影响规律研究。结果表明,在不同Re条件下,随着各向异性Kelvin泡沫H/D的减小,其泡沫内部的流动阻力及努塞尔数均增大,且随着Re的增大,对流换热的作用增强,H/D的影响也更为明显。此外,相比于流动阻力,结构传热性能受H/D的影响变化速率更大,由此造成综合传热因子(j/f^(1/3.)与H/D成反比关系,即减小Kelvin胞元H/D可有效提高泡沫结构的综合传热性能。

关键词：各向异性 Kelvin泡沫流动阻力综合传热因子

mechanical Properties and Microstructure Characteris-tics of Laser Rapid Forming Rene88DT Superalloy

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稀有金属材料与工程 2011年第S4期40卷 278-282页

作者： Zhao Xiaoming1,2,Gong Shuili1,Lin Xin2,Chen Jing 2,Huang Weidong21Science and Technology on Power Beam Processes laboratory,AVIC Beijing Aeronautical Manufacturing Technology Research In-stitute,Beijing 100024,china2state {3. laboratory of Solidification Processing,Northwestern Polytechnical university,Xi’an 710072,china AVIC Beijing Aeronaut Mfg Technol Res Inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China Northwestern Polytech Univ State Key Lab Solidificat Proc Xian 710072 Peoples R China

Nickel-based superalloy Rene88DT,has been laser-deposited using laser rapid forming (LRF) *** mechanical properties and microstructure characteristics of LRF Rene88DT at 25℃ and 750℃ were *** results shows that both strength and ductility of LRF Rene88DT can be improved significantly by the integration of optimized heat treatment (solution treatment (1160℃,2h/AC) + aging (760℃,8h/AC)) and the HIP treatment(1160℃,2h/200MPa).25℃ tensile properties is comparable to that of the Powder Metallurgy *** 750℃ tensile strength and ductility are also comparable to those of the Powder Metallurgy standard,but the yield strength is still a little lower at 750℃.As compared with the as-deposited state,g' precipitates of LRF Rene88DT are evolved gradually to be spherical in shape and uniformly distribute in the g matrix after optimized heat treatment and HIP *** surface shows that crack initiates at the edge for all the samples of LRF Rene88DT after tensile *** deformation is found to be homogeneous in the whole *** phenomenon exists near the fracture surface,which corresponds with the superior strength and ductility of LRF Rene88DT.

关键词： laser rapid forming Rene88DT mechanical properties microstructure characteristics

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***法制备c-BN膜的研究

无机材料学报 1999年第4期14卷 607-612页

作者：张晓玲胡奈赛何家文西安交通大学金属材料强度国家重点实验室

采用ＦＴＩＲ、ＴＥＭ、ＳＥＭ等技术，对在渗硼层表面经ｒｆ ＰＣＶＤ沉积的ＢＮ膜进行了研究试验证明，与采用Ｎ２气和Ｈ２气相比，以Ａｒ＋１０ｖｏｌ％Ｈ２作为载气，所获得的膜层ｃ ＢＮ... 详细信息

采用ＦＴＩＲ、ＴＥＭ、ＳＥＭ等技术，对在渗硼层表面经ｒｆ ＰＣＶＤ沉积的ＢＮ膜进行了研究试验证明，与采用Ｎ２气和Ｈ２气相比，以Ａｒ＋１０ｖｏｌ％Ｈ２作为载气，所获得的膜层ｃ ＢＮ含量最高，膜厚最大，可达４６μｍ，且膜基结合良好而以Ｎ２气或Ｈ２气为载气时，前者会导致膜基结合力大大下降，后者会引起沉积速度明显降低结果表明，对于ＰＣＶＤ过程，控制ｃ ＢＮ形成的主要因素是离子轰击能量的转移，而不是氢的选择溅射过程试验获得的膜层由ａ ＢＮ和ｃ ＢＮ组成，ｃ ＢＮ的尺寸为２０

关键词： c-BN膜 PCVD 镀膜制备

公铁两用运输车连挂冲击下的纵向载荷传递规律研究

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振动工程学报 2024年第2期37卷 276-285页

作者：董浩李映辉祝笈陆强张显峰刘鹏飞成都大学高等研究院四川成都610106 中车眉山车辆有限公司科创中心四川眉山620032 西南交通大学力学与航空航天学院四川成都611756 石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室河北石家庄050043

针对中国拟自助研发设计的公铁两用运输车,在编组连挂时由车钩经转向架传递至车体的载荷,其传递路径及规律尚不明确的问题,进行了试验测试与仿真研究。该车型的转向架在纵向能传递载荷的部件包括牵引板与抗蛇行减振器装置,需掌握载荷传... 详细信息

针对中国拟自助研发设计的公铁两用运输车,在编组连挂时由车钩经转向架传递至车体的载荷,其传递路径及规律尚不明确的问题,进行了试验测试与仿真研究。该车型的转向架在纵向能传递载荷的部件包括牵引板与抗蛇行减振器装置,需掌握载荷传递路径及其大小以便为后续结构部件的强度考核提供支撑。试验中,对转向架可能传递纵向载荷的部件进行了布点和载荷测试。仿真研究中,根据铁道车辆多体动力学理论与建模方法,建立了3.体4转向架的编组模型,模拟碰撞机车为含质量与速度的简化质量块。建立了抗蛇行减振器装置的力学模型,其力学结构为阻尼与刚度的串联模型;而构架到车体的纵向连接部件为牵引板⁃抗蛇行减振器装置的并联结构。运用多体动力学软件SIMPACK进行求解。结果表明:车钩与牵引板所受纵向载荷会随着碰撞体冲击速度的增大而增大,仿真结果略小于试验结果,但规律一致,且牵引板所受冲击载荷小于车钩载荷;而抗蛇行减振器装置结点几乎不受纵向载荷,与牵引板受载相比可忽略不计。由试验与仿真结果对比分析,明确了冲击载荷经车钩传递至车体时,几乎完全通过转向架上的牵引板传递,抗蛇行减振器装置作用很小,相关结果能够用于该车结构的优化设计及为部件强度校核提供载荷谱。

关键词：车辆系统动力学公铁两用运输车连挂冲击载荷传递路径

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激光复合加工硬脆性材料研究进展综述

机械工程学报 2024年第9期60卷 168-188页

作者：温秋玲杨野黄辉黄国钦胡中伟陈金鸿汪晖吴贤华侨大学制造工程研究院厦门361021 高性能工具全国重点实验室(华侨大学) 厦门361021 华侨大学机电及自动化学院厦门361021

玻璃、半导体、蓝宝石、陶瓷和硬质合金等硬脆性材料被广泛应用于建筑、生物医疗、航空航天、集成电路、新能源、光电显示、轨道交通、海洋等领域。但是其高硬度、大脆性、高耐磨性和耐腐蚀等特性也给它们的加工带来巨大挑战。目前,机... 详细信息

玻璃、半导体、蓝宝石、陶瓷和硬质合金等硬脆性材料被广泛应用于建筑、生物医疗、航空航天、集成电路、新能源、光电显示、轨道交通、海洋等领域。但是其高硬度、大脆性、高耐磨性和耐腐蚀等特性也给它们的加工带来巨大挑战。目前,机械加工、离子束加工、化学蚀刻、激光加工等方式是加工硬脆性材料的主要方法。但是这些加工方式依然存在加工效率和加工质量不可兼得的瓶颈问题。为此,研究人员提出了将激光加工和其他加工方式结合起来的复合加工方法,旨在实现硬脆性材料的高质量和高效率加工。概述了主流的基于激光复合的硬脆材料加工方法,主要包括其他方式辅助激光加工、激光辅助其他方式加工、激光辅助激光加工;重点阐述了这些激光复合加工技术的加工原理、研究现状和加工效果;总结了不同激光复合加工方法的优势、局限性和应用场景,最后对激光复合加工硬脆性材料的未来发展趋势提出了展望。

关键词：激光复合加工硬脆性材料加工效率加工质量微结构

High-temperature Thermo-oxidative Aging of Vulcanized Natural Rubber Nanocomposites:Evolution of Microstructure and mechanical Properties

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Chinese Journal of Polymer Science 2023年第8期41卷 1287-1297,I0010页

作者： Zhou-xian Li Yi-Ran Kong xiang-Fei Chen Ya-Jiang Huang Ya-Dong Lv Guang-xian Li College of polymer science and engineering State key laboratory of polymer materials engineering of ChinaSichuan UniversityChengdu 610065China

The aging of natural rubber(NR)at high temperatures will seriously affect its service lifetime in many key *** the present work,the changes in microstructure and mechanical properties of semi-efficient vulcanized NR/carbon black(CB)vulcanizates during thermooxidative aging at high temperatures(150-200℃)and a moderate temperature(95℃)were *** high temperatures,a two-stage aging behavior,which was characteristic of a first rapid decline and then a continuous rise in the crosslinking density(ve),was identified and was found to be closely related to the depletion behavior of *** surface cracking behavior observed in the second stage of high-temperature aging was discussed in terms of the grafting reaction of macromolecular radicals on CB particles and thermal *** contrast,the aging of NR at moderate temperatures was much mild,which featured a continuous increase in ve and an oxidation mechanism dominated by peroxy radicals attacking double *** general,the mechanical properties of NR vulcanizates during high-temperature aging depended on the competition effects of structural evolution in the crosslinked network and oxidation-induced chain scission.

关键词： Natural rubber nanocomposites High-temperature Thermo-oxidative aging

A reduced-order-model-based multiple-in multiple-out gust alleviation control law design method in transonic flow

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Science china(Technological Sciences) 2014年第2期57卷 368-378页

作者： CHEN Gang WANG xian LI YueMing state key laboratory for Strength and Vibration of {3. Structures School of Aerospace Xi'an Jiaotong University

Gust alleviation is very important to a large flexible aircraft.A nonlinear low-order aerodynamic state space model is required to model the nonlinear aeroelastic responses due to *** on the proper orthogonal decomposition method,a reduced order modeling of gust loads was *** then the open-loop and closed-loop reduced order state space model for the transonic aeroelastic system was *** static output feed back control scheme was used to design a simple multiple-in multiple-out(MIMO)gust alleviation control *** control law was demonstrated with the Goland+wing model with four control *** simulation results of different discrete gusts show the capability and good performance of the designed MIMO controller in transonic gust alleviation.

关键词： transonic gust alleviation reduced order model proper orthogonal decomposition static output feed back

Periodic Layered Structure Formed during Interfacial Reaction

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Journal of Iron and Steel Research International 2016年第11期23卷 1127-1133页

作者： xian-man ZHANG Hong-feng LUO Liu-yong SHI Institute of Electrical and mechanical Engineering Hainan University

A review of the periodic layered structure （PLS） formed during reactive diffusion was presented. The formation of PLS is a very interesting and complex phenomenon during the reactive diffusion process. It was firstly discovered occasionally. The formation of PLS has been reported in various solid state diffusion couples such as Zn/ Ni3.Si, Mg/SiO2, Zn/Cux Tiy and so on, and some controversial theoretical models and formation mechanism of PLS were put forward. However, there have been few reports about the PLS formed during hot dip. The development of PLS was reviewed, and the recent progress referring to the formation of PLS during the hot dip aluminizing of a no- vel Fe-Cr-B cast steel was especially introduced. However, not all of the borides could form PLS in their interracial reaction with molten Al. PLS only formed at the Cr-rich Fe2B/Al interface, while Mo-rich Fe2B fractured. A general qualitative description for the interracial reaction of Fe-Cr-B cast steel with molten Al was represented. Further inves- tigation on the constituents of the alternating phases and formation mechanism of PLS needs to be done. At last, the development trends of PLS were proposed.

关键词： periodic layered structure interfacial reaction reactive diffusion formation mechanism Fe-Cr-B cast steel