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Effect of Thermal Cycling under Load on Martensite Transformation and Two-way Shape Memory Effect in a TiNi Alloy 被引量:1
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作者 Liming WANG, Yufeng ZHENG, Wei CAI, Xianglong MENG and Liancheng ZHAO School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第2期263-266,共4页
The effect of thermal cycling under loading on martensitic transformation and two-way shape memory effect was investigated for Ti-49.8 at, pet Ni alloy. It is shown that M(s), and M(f) temperature increase with increa... The effect of thermal cycling under loading on martensitic transformation and two-way shape memory effect was investigated for Ti-49.8 at, pet Ni alloy. It is shown that M(s), and M(f) temperature increase with increasing the number of cycles, while A(s) and A(f) temperature decrease during thermal cycling. The total strain at and permanent strain epsilon (p) increase with increasing applied stress and number of cycles. The two-way shape memory effect can be improved by proper thermal cycling training under loading, while excessively high applied stress results in the deterioration of TWSME. The reason for the changes in martensitic transformation characteristics and two-way shape memory effect during thermal cycling under loading is discussed based on the analysis of microstructure by TEM observations. 展开更多
关键词 TINI Effect of Thermal Cycling under load on Martensite Transformation and Two-way Shape Memory Effect in a TiNi Alloy
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Effect of Mild-calcined Coal Gangue Additionon Hot Strength and Refractoriness Under Loadof Ultra Low Cement Castablesin Al_2O_3-SiO_2 System
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作者 FENG Sisi ZHOU Ningsheng 《China's Refractories》 CAS 2011年第3期18-21,共4页
This work explored the way to improve hot modulus q/' rupture (HMOR) and refractoriness under load (RUL) by adding mild-calcined coal gangue (MCG) in Al2O3 -SiO2 ultra low cement (ULC) castables, making use o... This work explored the way to improve hot modulus q/' rupture (HMOR) and refractoriness under load (RUL) by adding mild-calcined coal gangue (MCG) in Al2O3 -SiO2 ultra low cement (ULC) castables, making use of the in-situ effect of the MCG during heating-up. The influence of respective additions of 5%, 10% and 1.5% of the MCG powders calcined at 700℃ was investigated on HMOR at 1400 ℃ and RUL of the castables. With increased addition of the MCG, HMOR and RUL become significantly enhanced. At 10% of the MCG addition, HMOR reaches 3 MPa, as compared to 0. 3 MPa in the case of no MCG addition. RUL of the specimens dried at 110 ℃for 24 h can be increased by some 270 ℃ with 10% of the MCG addition. RUL 0.11 the specimens preheated at 1 500℃ for 3 h maintains the growth trend with the MCG addition increasing. The microstructure of the heated castable samples was investigated by means of SEM. The in-situ formed needle-like and interlaced mullite in the matrix is contributive to the tmprovement. 展开更多
关键词 Coal gangue Hot modulus of rupture Refractoriness under load Ultra low cement castable Alumina - silica system
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Preparation of Reference Samples for Refractoriness Under Load(Non-differential,with Rising Temperature) of Refractories
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作者 WANG Xiufang 《China's Refractories》 CAS 2013年第2期29-32,共4页
The preparation of reference samples for refractoriness under load ( non-differential, with rising temperature) of refractories was discussed. According to features and application of reference samples, quartz glass... The preparation of reference samples for refractoriness under load ( non-differential, with rising temperature) of refractories was discussed. According to features and application of reference samples, quartz glass was chosen as a stand-by reference material for uniformity and stability tests. Then, the true value was fixed by gathering the testing results from many labs with stable testing levels and reliable testing results in China. The testing results from these labs were used for normality test by Shapiro-wilk method; and for abnormality value test by Grubbs method, for equal observation test by Cochran method. After confirming no abnormality values among the testing results from the labs. the average values of reference samples were calculated and the uncertainty was appraised. The results show that the standard value of reference samples is 1 386 ℃ and the expanded uncertainty is 12 ℃. 展开更多
关键词 reference sample refractories test refractoriness under load
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Test Method for Refractoriness Under Load of Refractory Products(Non-differential,with Rising Temperature)
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作者 Wang Jing,Zhang Xiaohui,Yu Lingyan 《China's Refractories》 CAS 2012年第3期38-40,共3页
This standard specifies the definitions, theory, apparatus, specimens, procedures, test results and disposal, test error and report of test method for refractoriness under load of refractory products (non-differentia... This standard specifies the definitions, theory, apparatus, specimens, procedures, test results and disposal, test error and report of test method for refractoriness under load of refractory products (non-differential, with rising temperature). 展开更多
关键词 Test Method for Refractoriness under load of Refractory Products Non-differential with Rising Temperature
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An Efficient Framework for Utilizing Underloaded Servers in Compute Cloud
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作者 M.Hema S.Kanaga Suba Raja 《Computer Systems Science & Engineering》 SCIE EI 2023年第1期143-156,共14页
In cloud data centers,the consolidation of workload is one of the phases during which the available hosts are allocated tasks.This phenomenon ensures that the least possible number of hosts is used without compromise ... In cloud data centers,the consolidation of workload is one of the phases during which the available hosts are allocated tasks.This phenomenon ensures that the least possible number of hosts is used without compromise in meeting the Service Level Agreement(SLA).To consolidate the workloads,the hosts are segregated into three categories:normal hosts,under-loaded hosts,and over-loaded hosts based on their utilization.It is to be noted that the identification of an extensively used host or underloaded host is challenging to accomplish.Thresh-old values were proposed in the literature to detect this scenario.The current study aims to improve the existing methods that choose the underloaded hosts,get rid of Virtual Machines(VMs)from them,andfinally place them in some other hosts.The researcher proposes a Host Resource Utilization Aware(HRUAA)Algorithm to detect those underloaded and place its virtual machines on different hosts in a vibrant Cloud environment.The mechanism presented in this study is contrasted with existing mechanisms empirically.The results attained from the study estab-lish that numerous hosts can be shut down,while at the same time,the user's workload requirement can also be met.The proposed method is energy-efficient in workload consolidation,saves cost and time,and leverages active hosts. 展开更多
关键词 Workload consolidation energy consumption under load server resource utilization
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Shape design of the reinforcement for bending load-carrying capacity of under-matched butt joint under four-point bending load 被引量:1
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作者 王佳杰 杨建国 +3 位作者 张敬强 董志波 方洪渊 刚铁 《China Welding》 EI CAS 2012年第3期50-54,共5页
To improve the bending load-carrying capacity ( BLCC) of under-matched butt joint under four-point bending load in the elastic stage, the shape design of the reinforcement is studied based on the theoretics of mecha... To improve the bending load-carrying capacity ( BLCC) of under-matched butt joint under four-point bending load in the elastic stage, the shape design of the reinforcement is studied based on the theoretics of mechanics of materials. The concept, criterion, realization condition and design proposal of equal bending load-carrying capacity (EBLCC) are put forward. The theoretical analysis results have been verified by the finite element method. The simulation results are coincident basically with the ones of theoretical analysis. The research results show that the shape design of the reinforcement of EBLCC can improve BLCC of under-matched butt joint and the unilateral-side type reinforcement can replace double-side symmetry 展开更多
关键词 under-matched joint equal bending load-carrying capacity shape design of the reinforcement finite elementmethod
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Novel Models and Algorithms of Load Balancing for Variable-structured Collaborative Simulation under HLA/RTI 被引量:4
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作者 YUE Yingchao FAN Wenhui +1 位作者 XIAO Tianyuan MA Cheng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第4期629-640,共12页
High level architecture(HLA) is the open standard in the collaborative simulation field. Scholars have been paying close attention to theoretical research on and engineering applications of collaborative simulation ba... High level architecture(HLA) is the open standard in the collaborative simulation field. Scholars have been paying close attention to theoretical research on and engineering applications of collaborative simulation based on HLA/RTI, which extends HLA in various aspects like functionality and efficiency. However, related study on the load balancing problem of HLA collaborative simulation is insufficient. Without load balancing, collaborative simulation under HLA/RTI may encounter performance reduction or even fatal errors. In this paper, load balancing is further divided into static problems and dynamic problems. A multi-objective model is established and the randomness of model parameters is taken into consideration for static load balancing, which makes the model more credible. The Monte Carlo based optimization algorithm(MCOA) is excogitated to gain static load balance. For dynamic load balancing, a new type of dynamic load balancing problem is put forward with regards to the variable-structured collaborative simulation under HLA/RTI. In order to minimize the influence against the running collaborative simulation, the ordinal optimization based algorithm(OOA) is devised to shorten the optimization time. Furthermore, the two algorithms are adopted in simulation experiments of different scenarios, which demonstrate their effectiveness and efficiency. An engineering experiment about collaborative simulation under HLA/RTI of high speed electricity multiple units(EMU) is also conducted to indentify credibility of the proposed models and supportive utility of MCOA and OOA to practical engineering systems. The proposed research ensures compatibility of traditional HLA, enhances the ability for assigning simulation loads onto computing units both statically and dynamically, improves the performance of collaborative simulation system and makes full use of the hardware resources. 展开更多
关键词 static load balancing dynamic load balancing variable-structure collaborative simulation under HLA/RTI multi-objective optimization ordinal optimization
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基于截面增大法的扣放角钢焊接加固负载H型钢的轴压承载力研究
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作者 刘红波 张卓航 +3 位作者 陈志华 陈蕙芸 曹爽秋 张清沛 《天津大学学报(自然科学与工程技术版)》 EI CAS CSCD 北大核心 2024年第5期530-543,共14页
负载下焊接加固是既有结构加固的重要形式,然而当前对加固形式及加固效果的研究仍然较为缺乏.因此,提出了一种新型负载焊接加固构造,设计了8组扣放角钢焊接加固H型钢试验.研究了焊接过程中的截面应力重分布规律以及焊接加固H型钢柱的轴... 负载下焊接加固是既有结构加固的重要形式,然而当前对加固形式及加固效果的研究仍然较为缺乏.因此,提出了一种新型负载焊接加固构造,设计了8组扣放角钢焊接加固H型钢试验.研究了焊接过程中的截面应力重分布规律以及焊接加固H型钢柱的轴压力学性能.试验中加固构件的截面为加固前的1.53倍~1.55倍,焊接加固后构件极限承载增大为加固前的1.74倍~1.90倍;加固构件和原构件协同工作,获得了良好的加固效果,虽然焊接热输入降低了构件焊缝间隔处的屈曲应力,但负载加固的构件表现出相对零载加固构件更高的极限承载力.随后建立并验证了一种新型焊接加固H型钢柱的数值模拟方法,探究了不同截面面积加固构件的加固效果;揭示了不同焊缝间隔以及焊接热效应对加固构件极限承载力的影响,并建立了相应的设计方法. 展开更多
关键词 H型钢 轴压性能 负载焊接 应力重分布 加固后力学性能 数值模拟方法
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负载下活性粉末混凝土钢筋网加固足尺混凝土柱轴压性能试验研究
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作者 卜良桃 周恭慧 杜国强 《建筑结构》 北大核心 2024年第10期87-93,133,共8页
为提高负载下钢筋混凝土(RC)柱的轴心抗压性能,使用活性粉末混凝土钢筋网(RPCSM)对负载下的RC足尺柱进行加固,设计制作了7根RC方柱试件,其中1根未加固对比柱、1根端部箍筋加密加固柱、2根RPCSM加固柱、3根端部箍筋加密RPCSM加固柱。考... 为提高负载下钢筋混凝土(RC)柱的轴心抗压性能,使用活性粉末混凝土钢筋网(RPCSM)对负载下的RC足尺柱进行加固,设计制作了7根RC方柱试件,其中1根未加固对比柱、1根端部箍筋加密加固柱、2根RPCSM加固柱、3根端部箍筋加密RPCSM加固柱。考虑加固层厚度、钢筋网配筋率和端部箍筋加密对轴心受压RC柱性能的影响,进行了试验研究并分析了各试件的破坏模式、荷载-变形关系和应变变化规律。结果表明:加固柱的承载力提高了2.81~3.82倍;原混凝土柱与RPCSM加固层界面粘结可靠,共同工作良好;随着钢筋网配筋率的提高以及加固层厚度的增加,端部箍筋加密后整体性的提高,承载力和轴向变形能力提高,但延性有所下降。结合规范和破坏机理,给出了承载力计算公式,以促进该加固技术的推广。 展开更多
关键词 负载下加固 活性粉末混凝土 钢筋混凝土足尺柱 轴压性能 钢筋网 配筋率
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新型等离子体点火技术在火电灵活性中的应用分析 被引量:3
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作者 龚泽儒 王晓娜 +4 位作者 邹鹏 宋林波 吕俊复 朱新龙 郑艳丽 《锅炉技术》 北大核心 2024年第1期50-54,共5页
近年来在国家政策的主导下,风电等新能源得到了快速发展,新能源的消纳问题也随之凸显出来,灵活性调峰是解决这一问题的有效措施。等离子体点火技术是一项卓有成效的低负荷稳燃措施,可满足深度调峰需求,有效提高火电机组对新能源发电的... 近年来在国家政策的主导下,风电等新能源得到了快速发展,新能源的消纳问题也随之凸显出来,灵活性调峰是解决这一问题的有效措施。等离子体点火技术是一项卓有成效的低负荷稳燃措施,可满足深度调峰需求,有效提高火电机组对新能源发电的消纳能力。针对传统等离子体技术在火电灵活性应用中存在的问题,提出一种新型等离子体点火技术。该技术可使发生器阴极寿命提升至500 h以上,阳极寿命提升至1000 h以上;提高了煤质适应性,可适用于大部分燃用烟煤的电厂;而且点火过程中对燃烧器内燃强度有较好的控制,不易发生超温结焦现象。 展开更多
关键词 火电灵活性 等离子体点火 深度调峰 低负荷稳燃
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铝酸盐水泥结合莫来石不定形浇注料耐高温性能研究
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作者 李宣霖 文华 +3 位作者 周锦程 雷旭 范伟 蒋李志鸿 《新型建筑材料》 2024年第8期112-116,122,共6页
采用不同类型的铝酸盐水泥与电熔莫来石制成莫来石不定形耐火浇注料,研究了在不同温度煅烧后的线变化率、显气孔率、体积密度、力学性能及荷重软化温度的变化,采用XRD、SEM及EDS对物相组成及微观形貌进行分析。结果表明,线变化率在不同... 采用不同类型的铝酸盐水泥与电熔莫来石制成莫来石不定形耐火浇注料,研究了在不同温度煅烧后的线变化率、显气孔率、体积密度、力学性能及荷重软化温度的变化,采用XRD、SEM及EDS对物相组成及微观形貌进行分析。结果表明,线变化率在不同温度煅烧后均呈收缩的趋势,显气孔率随煅烧温度升高不断增大,体积密度随煅烧温度升高先减小而后增大;莫来石质浇注料经不同高温煅烧后,其抗折强度随温度升高不断提高,抗压强度随温度升高不断降低;使用CA80水泥、CA70水泥制备的耐火浇注料荷重软化温度最高,分别为1462、1442℃。 展开更多
关键词 铝酸盐水泥 莫来石 不定形浇注料 荷重软化温度
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考虑构网型风电频率响应的电力系统低频减载策略研究
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作者 邹小明 李强 +2 位作者 汪成根 贾勇勇 汤奕 《可再生能源》 CAS CSCD 北大核心 2024年第8期1089-1095,共7页
大规模构网型风电机组并网会改变电力系统频率响应特性,而传统低频减载策略尚未计及构网型风电机组的影响,可能导致大功率缺额后的系统减载量不合理。文章提出一种考虑构网型风电频率响应的电力系统低频减载策略。首先,基于构网型风电... 大规模构网型风电机组并网会改变电力系统频率响应特性,而传统低频减载策略尚未计及构网型风电机组的影响,可能导致大功率缺额后的系统减载量不合理。文章提出一种考虑构网型风电频率响应的电力系统低频减载策略。首先,基于构网型风电虚拟惯量和一次调频控制模型,建立计及构网型风电频率响应的系统频率响应简化模型;其次,分析构网型风电的有功响应特性对系统不平衡功率量的影响,进而精细化估算用于指导电网多轮次减载的不平衡功率量,从而提出自适应低频减载实施策略;最后,通过算例分析,验证了文章所提低频减载策略的可行性和有效性。 展开更多
关键词 构网型风电机组 虚拟惯量 一次调频 功率缺额 低频减载
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煤蠕变过程电磁辐射频谱特征实验研究
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作者 范鹏宏 聂百胜 《中国煤炭》 北大核心 2024年第7期105-114,共10页
为了研究煤在单轴蠕变加载条件下,电磁辐射频谱变化的响应规律,分别测试了不同煤种在单轴载荷下,垂直层理方向上短时蠕变过程中全阶段的电磁辐射频谱的变化特征,并讨论了其变化规律。研究结果表明,在单轴蠕变分级加载的过程中,煤体的电... 为了研究煤在单轴蠕变加载条件下,电磁辐射频谱变化的响应规律,分别测试了不同煤种在单轴载荷下,垂直层理方向上短时蠕变过程中全阶段的电磁辐射频谱的变化特征,并讨论了其变化规律。研究结果表明,在单轴蠕变分级加载的过程中,煤体的电磁辐射频率及其振幅总体趋势出现了相似的变化规律,并且各个阶段的频率及其振幅也有各自相似的变化规律。在整个蠕变过程中煤体的电磁辐射信号频率整体处在低频阶段,主要集中于0~0.5 MHz,且加速蠕变变形阶段的电磁辐射频带范围大于减速和等速蠕变变形阶段。在减速和等速蠕变变形期,煤体的电磁辐射频率的振幅变化均处在低振幅阶段;在加速蠕变变形期,可能由于煤体损伤的加剧,使得电磁辐射频率的振幅变化出现较大幅度的波动;在加速蠕变变形末期直到样品临近断裂前,煤体的电磁辐射频率的振幅值会出现增大减小增大的趋势。研究结果可为煤岩流变突变过程中损伤破坏信息的准确感知及煤岩动力灾害的智能监测与预警提供一定的实验和理论依据。 展开更多
关键词 煤岩动力灾害 单轴分级加载 短时蠕变 电磁辐射 频谱特征
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考虑输电网与柔性互联配电网交互影响的可靠性评估方法 被引量:1
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作者 史明明 刘瑞煌 +2 位作者 张宸宇 朱卫平 葛雪峰 《电力工程技术》 北大核心 2024年第4期77-87,共11页
对输电网与柔性互联配电网组成的输配电网络整体采用故障枚举法进行可靠性评估时,除去分析输电网与配电网内部故障对各自供电可靠性的影响之外,还须考虑故障场景下输电网与配电网间的交互影响。文中在现有输电网与配电网各自独立的可靠... 对输电网与柔性互联配电网组成的输配电网络整体采用故障枚举法进行可靠性评估时,除去分析输电网与配电网内部故障对各自供电可靠性的影响之外,还须考虑故障场景下输电网与配电网间的交互影响。文中在现有输电网与配电网各自独立的可靠性评估方法基础上,提出针对输配电网络整体的可靠性评估方法。所提方法可计及故障条件下输电网与配电网运行状态间的相互关联,将输电网故障后的节点负荷减载细化为配电网优化后的负荷切除方案,提升输电网可靠性评估结果精度,并将应对输电网故障导致的配电网负荷损失纳入配电网可靠性评估。此外,在输电网可靠性评估中计及了配电网内部故障导致的输电网节点供电负荷损失及其对输电网运行可靠性造成的影响。针对输配电网络整体,基于故障枚举采用解析法计算得到输配电网络可靠性指标,算例分析结果验证了所建立可靠性评估模型的有效性。 展开更多
关键词 可靠性评估 柔性互联配电网 输电网 故障枚举 负荷减载 故障重构
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基于ABAQUS的负载下碳纤维布受弯工字形钢梁有限元分析
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作者 谷夏菲 《工程质量》 2024年第3期29-33,共5页
随着软件有限元模拟技术和经济的不断发展,ABAQUS软件作为工程应用中大型有限元软件,经过有限元分析,均清晰地对问题进行了诠释。论文基于ABAQUS有限元软件,分析模拟研究了负载下,不同加固参数对加固受弯工字形钢梁力学性能的影响,为工... 随着软件有限元模拟技术和经济的不断发展,ABAQUS软件作为工程应用中大型有限元软件,经过有限元分析,均清晰地对问题进行了诠释。论文基于ABAQUS有限元软件,分析模拟研究了负载下,不同加固参数对加固受弯工字形钢梁力学性能的影响,为工程实际提供参考借鉴作用。具体结论主要为以下几点。不同负载水平(负载0%、30%、45%、60%、70%)的钢梁,加固参数相同,试件组合体承载力有限元模拟值与试验值误差在5%以内,吻合良好。负载水平不同,其最终破坏荷载也不尽相同,荷载挠度曲线规律相似,但负载水平的提高而破坏荷载有所下降。负载条件不同,不同加固层数下的荷载-挠度曲线近似相近,试件承载力与加固层数呈正比,但加固层数至一定程度,承载力增长幅度基本呈平稳趋势。当加固层数达到两层时,加固效果良好。随着改变碳纤维布长度,其荷载-挠度曲线规律基本相似,且随着碳纤维长度的增加,承载力也有一定提高。 展开更多
关键词 负载下 碳纤维布 荷载-挠度 生死单元 有限元
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南宁盆地特殊地层静压随钻跟管桩适应性及单桩承载力特性研究
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作者 彭伍连 罗冲 +3 位作者 韩伟 张信贵 唐运民 严利娥 《化工矿产地质》 CAS 2024年第2期179-186,共8页
为了研究静压随钻跟管桩在南宁盆地特殊地层的适应性及单桩承载特性,对现场4根直径800mm的静压随钻跟管桩进行静载及低应变反射波法试验。研究结果表明:各地层中的试验桩承载力均能满足设计要求且均属于Ⅰ类桩,桩身回弹率较高,说明各试... 为了研究静压随钻跟管桩在南宁盆地特殊地层的适应性及单桩承载特性,对现场4根直径800mm的静压随钻跟管桩进行静载及低应变反射波法试验。研究结果表明:各地层中的试验桩承载力均能满足设计要求且均属于Ⅰ类桩,桩身回弹率较高,说明各试验桩仍具有较大的承载潜力;未进行破坏性试验时各地层中单桩承载力综合增强系数均大于1.00,以经验公式确定静压随钻跟管桩的单桩竖向承载力时应乘以相应的增强系数。基于以上研究,将静压随钻跟管桩工艺应用于实际工程,经验收检测表明,各项目受检基桩的桩身质量完好,承载力均满足设计要求,且仍具有一定的承载力富余量,良好的实际工程应用效果表明该工艺具有良好的适用性以及较高的推广使用价值。 展开更多
关键词 静压随钻跟管桩 静载试验 低应变 单桩承载力 适应性
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Hot Load Deformation of Light-weight Insulating Fireclay Bricks
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作者 HAN Bo, LI Yushan 《China's Refractories》 CAS 2012年第4期13-16,共4页
The hot load deformation tests of four kinds of insulating fireclay bricks were carried out using a high temperature creep furnace from Sinosteel Luoyang hlstitute of Refractories Reseorch Co. , Ltd. The testing load ... The hot load deformation tests of four kinds of insulating fireclay bricks were carried out using a high temperature creep furnace from Sinosteel Luoyang hlstitute of Refractories Reseorch Co. , Ltd. The testing load was fixed at 0. 069 MPa and the total testing time was with- in 6 h including the holding time of 1.5 h. The hot load defi〉rmation process of insulating fireclay bricks can be divided into three steps : ( 1 ) expansion step from room temperature to RUL Tmax;( 2 ) quick shrinkage step be- tween. RUL T and Ttest; 3 ) relatively slow shrinkage step during holding process. The deformation rate at the beginning of holding process (D0h) should be controlled withi, +0. 1%. The hot load deformation testing tem- perature of insulating fireclay bricks was optimized as the value of RUL T plus 220℃. 展开更多
关键词 insulating fireclay bricks hot load deformation refiactoriness under load CREEP
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负载对某钢结构电视塔焊接加固的影响分析
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作者 贺然 李欣 《特种结构》 2024年第3期66-71,共6页
为研究负载对某钢结构电视塔焊接加固的影响,利用midas Gen软件中的施工阶段分析功能,分别建立整体梁单元模型及多尺度模型,考虑卸载加固及负载加固两种情况,得到不同初始负载下的构件极限承载力、整体模型中构件的应力大小、分布及结... 为研究负载对某钢结构电视塔焊接加固的影响,利用midas Gen软件中的施工阶段分析功能,分别建立整体梁单元模型及多尺度模型,考虑卸载加固及负载加固两种情况,得到不同初始负载下的构件极限承载力、整体模型中构件的应力大小、分布及结构位移。计算结果表明,随着初始负载的增大,构件极限承载力变化不大,但整体模型中原构件受力增大,加固构件受力减小,加固效率降低。故进行加固设计时,应考虑初始负载的影响,可采用施工阶段分析辅助设计;焊接施工应在较小的风速下进行,保证原构件及加固构件能协同工作。 展开更多
关键词 钢结构电视塔 负载 焊接加固 施工阶段分析
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液体二氧化碳装置运行中存在问题与优化对策
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作者 王涛 《大氮肥》 CAS 2024年第2期90-93,108,共5页
液体二氧化碳装置以低温甲醇洗装置排放的高纯度二氧化碳尾气为原料气,通过脱除原料气中的水、硫化氢、羰基硫、氨气、甲醇等一些轻组分,把二氧化碳提纯到99.9%以上,气体经压缩、净化、液化,达到国家食品添加剂的标准后再制得高纯食品... 液体二氧化碳装置以低温甲醇洗装置排放的高纯度二氧化碳尾气为原料气,通过脱除原料气中的水、硫化氢、羰基硫、氨气、甲醇等一些轻组分,把二氧化碳提纯到99.9%以上,气体经压缩、净化、液化,达到国家食品添加剂的标准后再制得高纯食品级液体二氧化碳。分析该装置运行中残气排放引发现场可燃气体及有毒有害气体报警仪报警、吸收剂粉化及压缩机低负荷运行时能耗损失等问题,挖掘节能降耗措施,优化生产运行参数,确保装置经济、安全、稳定运行。 展开更多
关键词 液体二氧化碳装置 残气排放 吸附剂粉化 低负荷能耗
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高速动车组车下设备的吊耳动力学分析
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作者 丁杰 《西南交通大学学报》 EI CSCD 北大核心 2024年第1期168-176,共9页
为揭示CRH380AL高速动车组车下设备不同位置的吊耳产生裂纹差异很大的原因,开展实车运行工况下的振动和气动载荷测试,建立车下设备-车辆-轮轨-线路多重耦合大系统动力学模型,其中的车体和车下设备利用有限元法建立弹性体模型,轮轨子系... 为揭示CRH380AL高速动车组车下设备不同位置的吊耳产生裂纹差异很大的原因,开展实车运行工况下的振动和气动载荷测试,建立车下设备-车辆-轮轨-线路多重耦合大系统动力学模型,其中的车体和车下设备利用有限元法建立弹性体模型,轮轨子系统和转向架子系统使用多刚体动力学建模,轨道不平顺谱应用武汉至广州区间的实际测量数据,隧道通过和隧道交会等工况的气动载荷由八节车气动模型数值模拟获得,分析了车体弹性、气动载荷和螺栓刚度等因素对车下设备吊耳支反力的影响.研究表明:车下设备与车辆系统之间存在强烈的耦合行为,车下设备本身质量分布和车体弹性耦合效应导致4号吊耳垂向动态载荷最大,与现场故障裂纹占比最高的情况对应;气动载荷对车下设备8号吊耳动态载荷存在明显影响;低频区域的吊耳动态载荷随螺栓刚度的增大而增大,垂向平均动载荷和最大动载荷分别为其余2个方向的4倍和6倍.基于线路和车辆耦合的动力学分析方法可为车下设备动态力学行为的设计和疲劳性能的优化提供理论支撑. 展开更多
关键词 高速列车 车下设备 吊耳 线路 气动载荷 刚柔耦合 动态载荷
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