17 research outputs found

    Load Spectrum Compiling Based on Operation Section Recognition and Fatigue Life Prediction of Wheel Loader Axle Shaft

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    为改进轮式装载机可靠性及耐久性设计中数据清洗和分析的方法,以装载机半轴为对象,优化载荷信号去噪和作业段识别的方法。利用小波自适应阈值法去除实测载荷的噪声尖峰和突变信号,并通过迭代平滑滤波法搜寻单个作业周期内同步载荷信号的极值点,识别、划分作业段为"行走段-铲掘段"。结合雨流计数和频次外推法编制载荷谱,有限元静力分析,以及Miner准则对装载机半轴进行疲劳寿命分析。结果表明:雨流计数的均幅值结果符合正态分布和三参数威布尔分布的假设性检验,疲劳分析损伤最大节点出现在万向节叉连接处,其寿命为7.22×10^8次循环。结果证实了作业段智能识别法的便利性和准确性,为传动系统疲劳分析的数据处理提供了借鉴。In order to improve the method of data cleaning and data analysis in fatigue durability and modify reliability design of wheel loader,research on load signal denoising and operation section recognition of wheel loader axle shaft was conducted. In view of the shortcoming of residual noise and waveform distortion caused by traditional wavelet threshold analysis,an adaptive threshold denoising method was used. Operation sections were divided as"driving section-shoveling section"through searching the extreme points of synchronous load signal in one single work cycle after iterative smoothing filter. Based on one-dimensional program loading spectrum and the finite element analysis,the fatigue life of axle shaft was predicted using the Miner criterion. The result shows that rain flow counting results were consistent with Normal distribution and Weibull distribution hypothesis testing. And the maximum damage node appeared in the universal joint folk which fatigue life is 7. 22 × 10^8 times cycle. The result confirmed that the intelligent recognition method is convenient and accurate,which provides a reference method for data processing of fatigue analysis of wheel loader transmission system.福建省财政厅企业技术创新项目资

    Raman Spectroscopic Study on Mechanism of Aluminum Triphosphate Pigment

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    应用拉曼光谱研究了含有防锈颜料涂装特性的钢样 ,在此基础上探讨了三聚磷酸铝防锈颜料对A3钢的保护机理 .三聚磷酸铝溶解后能到达钢样表面 ,其离子可与铁离子化合形成三聚磷酸铁 .三聚磷铁能缓慢地通过化学键牢固地附着在钢样表面 ,最终在钢表面形成一层隔绝腐蚀介质和钢样的紧蜜保护膜阻止了腐蚀的继续发生从而达到保护的目的The painted steel sample whose coating contained anticorrosive pigment has been investigated by Raman spectroscopy.The protective mechanism of aluminum triphosphate pigment for A3 steel is proposed as follows: Aluminum triphosphate can be dissolved and arrive at the surface of the steel.The dissolved triphosphate ions can complex with ferric ions.And the new products,namely ferric triphosphate,can strongly adhere at the surface of the steel by chemical bonds slowly.At last,a compact protective film,which effectively separates the steel substrate from the aggressive media,is formed at the steel surface.作者联系地址:中国科学院福建物质结构研究所,中国科学院福建物质结构研究所,中国科学院福建物质结构研究所,中国科学院福建物质结构研究所,中国科学院福建物质结构研究所 福建厦门361012 ,福建厦门361012 ,福建厦门361012 ,福建厦门361012 ,福建厦门361012Author's Address: Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences,Xiamen 361012,Chin

    Electrochemical Impedance Spectroscopy Studies on Inhibitive Performance of Aluminum Triphosphate Pigment

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    利用电化学阻抗谱研究了方解石及三聚磷酸铝环氧涂层的耐蚀性能 ,并提出了它们的作用机理 .结果表明 ,方解石只起体质颜料作用 ,不具备缓蚀性能 ;而三聚磷酸铝因在钢基表面作用形成致密的保护膜则表现出优良的缓蚀性能 .The epoxy coatings on A3 steel sheets containing calcite or aluminum triphosphate (AlTP), were investigated by Electrochemical Impedance Spectroscopy (EIS). The results showed that calcite pigment is not an inhibitor, but an extender pigment, and that AlTP pigment can considerably enhance the protective performance of epoxy coating. The triphosphate ion at the interface between the steel substrate and the coating can complex with the corrosion product, such as ferric and ferrous ions, and form a compact protective film which effectively separates the steel substrate from the aggressive media.作者联系地址:中国科学院福建物质结构研究所!福建厦门361012,中国科学院福建物质结构研究所!福建厦门361012,中国科学院福建物质结构研究所!福建厦门361012,中国科学院福建物质结构研究所!福建厦门361012,中国科学院福建物质结构研究所!福建厦门361012Author's Address: Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Xiamen, 361012,Chin

    EFFECT of ION-SELECTIVE PHENOLIC COATINGS ON ELECTRO-CHEMICAL BEHAVIOUR of COPPER IN 3% NaClSOLUTION

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    利用掺杂离子交换体制备了含不同交换离子品种的阴离子选择性、阳离子选择性和双极性酚醛涂层,研究了涂装不同离子选择性酚醛涂层的铜电极在3%nACl溶液中的腐蚀电化学行为,讨论了各种离子选择性涂层对铜防护性能的差别,并与没有离子选择性的涂层作了比较。Anion-selective, cation-selective and bipolar phenolic coatings were prepared by mixing phenolic varnish with ion exchangers.MoO42- anion exchanger resin and ammonium molybdophosphate were utilized as anion and cation exchangers respectively.The bipolar coating consisted of an anion-selective inner layer on the metal side and a cation-selective outer layer on the solution side.The polarization curves and Nyquist plots of copper electrodes covered with various ion-selective phenolic coatings and nonionic-selective phenolic coating as contrast in 3% NaCl solution were measured by poltentio-dynamic method and EIS technique.The results indicated that, compared with the nonionic- selective coating, the anion-selective coating accelerated the propagation of metal corrosion, cation-selective coating decelerated corrosion propagation, and bipolar coating was the most corrosion-resistant among the Four types of phenolic coatings.With the bipolar coating, the anodic current was greatly suppressed, while no current blockage occurred in the cathodic direction.Thus there arose rectiFication of ion movement retarding the ionic current in the anodic direction.The rectiFication phenomenon blocked the Flow of anodic ion transport and led to metal passivation.This showed that the bipolar coating possessed some Function of passivation membrane and had important eFFect on the process of anodic dissolution.国家自然科学基金资助项目;金属腐蚀与防护国家重点实验室课

    A Study on AntiCorrosion Performance of IonSelective Phenolic Coatings for Carbon Steel by EIS

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    研究了涂有不同离子选择性酚醛层的碳钢试样在3%nACl溶液中的电化学交流阻抗谱,用不同的等效电路解析了不同涂层体系的频谱行为,讨论了不同离子选择性涂层对碳钢的防腐蚀性能,分析了各自的耐蚀机理。结果表明,双极性和阳离子选择性酚醛涂层对碳钢的防腐蚀性能比酚醛清漆好,而阴离子选择性酚醛涂层比酚醛清漆差。Abstract The anticorrosion performance of carbon steel painted with anionselective,cationselective and bipolar phenolic coatings,and phenrolic varnish (nonionicselective phenolic coating) as contrast in 3% NaCl solution,was investigated by electrochemical impedance spectroscopy (EIS) technique.The results showed that compared with nonionicselective phenolic coating, the anionselective phenolic coating accelerates the propagation of metal corrosion, whereas cationselective phenolic coating decelerates corrosion propagation, and bipolar phenolic coating is the most corrosionresistance among the fur types of phenolic coatings.国家自然科学基金;中国科学院腐蚀与防护国家重点实验室课

    Electrochemical and Corrosion Behaviour of A3 Steel Covered With Ion selective Organic Coating

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    采用动电位扫描极化曲线和电化学交流阻抗技术,研究了A3钢表面涂装阴离子选择性、阳离子选择性和双极性有机涂层在3%nACl溶液中的腐蚀和电化学行为,分析了不同离子选择性涂层对A3钢防蚀性能的差别,并探讨了其耐蚀机理Potentiodynamic method and electrochemical impedance spectroscopy technique were empoloyed to study the corrosion electrochemical behaviour of A3 steel covered with anion selective、 cation selective and bipolar organic coating ,and phenolic varnish (nonionic selective organic coating) as contrast, in 3% NaCl solution.The results indicate that,compared with phenolic varnish,anion selective organic coating accelerates the propagation of metal corrosion,whereas cation selective organic coating decelerates corrosion propagation, and bipolar organic coating is of the most corrosion resistance among the Four type organic coatings.国家自然科学基金;中国科学院腐蚀与防护国家重点实验室课

    煤炭地下气化关键力学问题的数值研究进展

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    煤炭资源的清洁高效利用已成为“双碳”背景下科学研究的重要方向和新课题.在众多相关技术中,煤炭地下气化技术近年来得到快速发展并展现出巨大潜力.然而,由于室内实验和现场试验的实施成本非常高,气化机理认识和控制运行工艺优化方面的研究均受到很大限制.近年来,运行成本低、操作简单、实施周期短的数值模拟方法成为重要的研究工具,得到越来越多的关注.由于煤炭地下气化过程极其复杂,数值模拟方法在数学建模和数值求解方面均面临巨大挑战.对此,本文开展了以下工作:对煤炭地下气化过程进行了详细分析,阐明各个运行空间的物质和关键问题,厘清煤炭地下气化的本质;归纳出流体动力学问题、热力学问题、材料应力问题以及化学反应动力学问题等4类关键力学问题;详细介绍每个关键力学问题数值研究的最新成果和发展历程;介绍煤炭地下气化数值研究的工程应用,并指出其发展趋势.本文工作对推动煤炭地下气化数值方法的发展以及指导我国煤炭地下气化先导试验设计和现场实施有积极的理论意义

    煤炭地下气化腔CO_2埋存的研究进展及发展趋势

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    CO_2捕集与埋存(CCS)可助力碳达峰、碳中和战略目标实现,是解决温室效应的重要手段.在众多地质埋存空间中,煤炭地下气化(UCG)后的气化腔近年来成为埋存研究的热点,但与传统埋存方式相比,相关工作仍处于理论探索阶段,缺乏现场实施案例.为推动该埋存方式的发展,文章从以下3方面开展工作.(1)介绍UCG和CO_2气化腔埋存的国内外研究进展,并将后者的发展划分为概念提出阶段、潜力评价和可行性分析阶段以及机理分析阶段,目前尚处于理论探索阶段.(2)从注入性、密闭性、经济性、储容量和CO_2埋存机理等多个角度出发,通过与其他埋存方式对比,分析了气化腔埋存的特点与优势:注入性良好;密闭性与未开发煤层类似,但更为复杂;显著节约CO_2运输成本;埋存潜力巨大;埋存机理非常复杂,需要考虑气化腔形态、边壁性质以及超临界CO_2与气化腔流体间复杂相互作用对注入和长期埋存过程的影响.(3)阐明CO_2气化腔埋存所涉及的关键科学问题和工程问题,并指出未来发展趋势.在以上工作的基础上,建议国家出台相关政策鼓励和支持UCG及后续的CO_2气化腔埋存,丰富CCS体系,推动煤炭资源的清洁化和低碳化利用.</p
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