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Evaluation of tool wear and cutting performance based on FEM simulation

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Chinese Journal of Aeronautics 2021年第4期34卷 140-152页

作者： Zhenyu SHI xin li Ningmin duan Qibiao YANG Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of EducationShandong UniversityJinan 250061China School of Mechanical Engineering Shandong UniversityJinan 250061China School of Mechanical Engineering Hubei University of TechnologyWuhan 430000China

An accurate estimation of tool wear morphology can provide the opportunity to investigate the influence of tool wear on cutting performance as well as reduce the overall production ***,tool wear prediction is still a very challenging research *** this paper,a novel method for simulating the actual chip formation and wear evolution thorough the 3 D finite element model has been carried *** order to improve the accuracy of simulation results,the influence of worn tool,stress and temperature distribution on wear rate are *** cutting experiment has been conducted by turning AISI1045 with uncoated carbide tools to validate the accuracy of the proposed *** comparison between experimental and simulation results show good agreement which proves the ability of the proposed model in forecasting the tool *** validated finite element model has been further utilized studying how the worn tool affects the cutting performance including actual cutting rake,stress distribution,cutting force and *** results of this paper not only provide a clear understanding of wear evolution between tool rake face and chip,but also are meaningful to optimize tool design and cutting parameters.

关键词： Finite element method Friction model Machining Stress distribution Wear

铁精粉中Al_2O_3的快速测定—铬天青S光度法

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山东冶金 2000年第2期22卷 50-51页

作者：王丽段心翠莱芜钢铁集团有限公司技术监督处山东莱芜271104

采用 Zn-EDTA掩蔽铁等干扰元素 ,在 p H5～ 6间 ,铝与铬天青 S生成水溶性的紫红色配合物 ,在波长 5 46nm处 ,进行光度测定。此法简便、快速。

关键词：铬天青S 光度法铁精粉 A12O3 测定

雾化吸入双黄连注射剂治疗上呼吸道感染效果的Meta分析

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药物流行病学杂志 2016年第10期25卷 627-631页

作者：李晓霞张俊坡李晓春耿鑫段金菊山西医科大学第二医院药学部太原030001 太原市中心医院药学部山西医科大学第二医院护理部山西医科大学药学院

目的：系统评价双黄连注射剂经雾化吸入治疗上呼吸道感染的有效性和安全性。方法：计算机检索中国知网（CNKI）、维普网（VIP）和万方数据库（Wan Fang Data）（检索年限为2000年1月1日-2015年11月15日）,收集所有双黄连雾化吸入治疗上... 详细信息

目的：系统评价双黄连注射剂经雾化吸入治疗上呼吸道感染的有效性和安全性。方法：计算机检索中国知网（CNKI）、维普网（VIP）和万方数据库（Wan Fang Data）（检索年限为2000年1月1日-2015年11月15日）,收集所有双黄连雾化吸入治疗上呼吸道感染的随机对照试验,按照纳入与排除标准独立筛选试验,对纳入研究进行质量评价,并用Stata 12.0软件进行统计分析。结果：共纳入16个研究,合计1 661例上呼吸道感染的患者;Cochrane系统评分均为B级。Meta分析结果显示：与对照组比较,双黄连注射剂雾化吸入在提高上呼吸道感染临床总有效率方面显示出较好疗效（OR=1.30,95%CI：1.13-1.50,P〈0.001）。仅1篇文献提及双黄连雾化组未发现不良反应,其他文献均未报道不良反应的结果。结论：双黄连注射剂雾化吸入治疗上呼吸道感染的疗效优于空白组、庆大霉素雾化组或庆大霉素加地塞米松雾化组,但其长期疗效和更全面的安全性尚需开展更多大样本、高质量的RCT加以验证。

关键词：双黄连注射剂雾化吸入上呼吸道感染系统评价

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基于AHP和因次分析法的工厂选址应用研究

淮阴工学院学报 2011年第3期20卷 84-88页

作者：王立秀段昕高宏波重庆交通大学管理学院重庆400074

厂址选择是企业建设的重要一环,关系到工厂在今后长期生产运营中的合理性、可靠性和经济性。针对工厂选址问题中的多种因素,分别运用层次分析法和因次分析法对其权重进行确定,阐述层次分析法和因次分析法应用于厂址选择的基本步骤,较好... 详细信息

厂址选择是企业建设的重要一环,关系到工厂在今后长期生产运营中的合理性、可靠性和经济性。针对工厂选址问题中的多种因素,分别运用层次分析法和因次分析法对其权重进行确定,阐述层次分析法和因次分析法应用于厂址选择的基本步骤,较好地将定性方法与定量方法结合起来,简化了计算过程。并结合实例,说明具体的优化方法,同时简单分析了两种方法的异同。该方法不仅能全面地考虑多种因素,而且计算简单,可以在工厂厂址选择时推广应用。

关键词：因次分析法层次分析法厂址选择

Topological Structure of Knotted Vortex lines in liquid Crystals

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Communications in Theoretical Physics 2007年第6期47卷 1129-1134页

作者： duan Yi-Shi ZHAO li ZHANG xin-Hui Institute of Theoretical Physics Lanzhou University Lanzhou 730000 China

In this paper, a novel decomposition expression for the U（1） gauge field in liquid crystals （LCs） is derived. Using this decomposition expression and the b-mapping topological current theory, we investigate the topological structure of the vortex lines in LCs in detail. A topological invariant, i.e., the Chern-Simons （CS） action for the knotted vortex lines is presented, and the CS action is shown to be the total sum of all the self-linking and linking numbers of the knot family. Moreover, it is pointed out that the CS action is preserved in the branch processes of the knotted vortex lines.

关键词： knotted vortex lines liquid crystals Chern-Simons action branch processes

On Universally Left-stability of ε-Isometry

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Acta Mathematica Sinica,English Series 2013年第11期29卷 2037-2046页

作者： ling xin BAO li xin CHENG Qing Jin CHENG duan Xu DAI School of Mathematical Sciences Xiamen University

Let X, Y be two real Banach spaces and ε≥0. A map f ： X → Y is said to be a standard ε-isometry if│││f/（x） - f（y）││ - ]ix - Y││x-y││ ε for all x,y C X and with f（O） = O. We say that a pair of Ban... 详细信息

Let X, Y be two real Banach spaces and ε≥0. A map f ： X → Y is said to be a standard ε-isometry if│││f/（x） - f（y）││ - ]ix - Y││x-y││ ε for all x,y C X and with f（O） = O. We say that a pair of Banach spaces （X, Y） is stable if there exists γ〉 0 such that, for every such ε and every standard v-isometry f ： X → Y, there is a bounded linear operator T ： L（f） → f（X） → X so that ││Tf（x） - x││ ≤γε for all x E X. X（Y） is said to be universally left-stable if （X, Y） is always stable for every Y（X）. In this paper, we show that if a dual Banach space X is universally left-stable, then it is isometric to a complemented w＊-closed subspace of ∞ （1） for some set F, hence, an injective space; and that a Banach space is universally left-stable if and only if it is a cardinality injective space; and universally left-stability spaces are invariant.

关键词： ε-Isometry linear isometry stability injective space Banach space

Water modeling on fluid flow and mixing phenomena in a BOF steelmaking converter

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Journal of Iron and Steel Research International 2024年第3期31卷 595-607页

作者： xin-yu Cai Hao-jian duan Ding-han li Anjun Xu li-feng Zhang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing 100083China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

A 1∶8 physical water model was constructed to investigate the fluid flow and mixing phenomena in the basic oxygen furnace(BOF)*** particle image velocimetry was employed to measure the velocity distribution of the bath and the high-speed camera was applied to capture the cavity shape in the combined blowing BOF *** mixing time for varied operating conditions was measured by the stimulus-response *** cavity depth increased with the decrease in the lance height and the increase in the top gas flow rate while the bottom blowing gas had little influence on the cavity *** minimum cavity depth was obtained under the condition of a 69.8 m^(3)/h top gas flow rate,a 287.5 mm lance height and a 0.93 m^(3)/h bottom blowing gas flow rate,which was 161.2 *** mixing time decreased as the lance height decreased and the top blowing gas flow rate *** mixing time was first decreased and then increased with the increase in the bottom gas flow *** the condition of 69.8 m^(3)/h gas flow rate of top blowing,the 287.5 mm lance height and the 0.93 m^(3)/h gas flow rate of bottom blowing,the mixing time in the converter was 48.65 *** empirical formula between the stirring power and the mixing time in the converter was calculated.

关键词： Water model Fluid flow Particle image velocimetry Mixing time BOF converter

Improvement of solidification model and analysis of 3D channel blockage with MPS method

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Frontiers in Energy 2021年第4期15卷 946-958页

作者： Reo KAWAKAMI xin li Guangtao duan Akifumi YAMAJI Isamu SATO Tohru SUZUKI Cooperative Major in Nuclear Energy Graduate School and Advanced Science and EngineeringFaculty of Science and EngineeringWaseda University3-4-1 OkuboShinjuku-kuTokyo169-8555Japan Department of Nuclear Engineering and Management The University of Tokyo7-3-1 HongoBunkyo-kuTokyo113-8656Japan Department of Nuclear Safety Engineering Faculty of EngineeringTokyo City University1-28-1 TamazutsumiSetagaya-kuTokyo158-0087Japan

In a severe accident of a nuclear power reactor,coolant channel blockage by solidified molten core debris may significantly influence the core degradations that *** moving particle semi-implicit(MPS)method is one of the Lagrangian-based particle methods for analyzing incompressible *** the study described in this paper,a novel solidification model for analyzing melt flowing channel blockage with the MPS method has been developed,which is suitable to attain a sufficient numerical accuracy with a reasonable calculation *** prompt velocity diffusion by viscosity is prioritized over the prompt velocity correction by the pressure term(for assuring incompressibility)within each time step over the“mushy zone”(between the solidus and liquidus temperature)for accurate modeling of solidification before fixing the coordinates of the completely solidified *** sustain the numerical accuracy and stability,the corrective matrix and particle shifting techniques have been applied to correct the discretization errors from irregular particle arrangements and to recover the regular particle arrangements,*** validate the newly developed algorithm,2-D benchmark analyses are conducted for steady-state freezing of the water in a laminar flow between two parallel ***,3-D channel blockage analyses of a boiling water reactor(BWR)fuel support piece have been *** results show that a partial channel blockage develops from the vicinity of the speed limiter,which does not fully develop into a complete channel blockage,but still diverts the incoming melt flow that follows to the orifice region.

关键词： boiling water reactor(BWR) severe accident channel blockage moving particle semi-implicit(MPS)method solidification*

3D printed labyrinth multiresonant composite metastructure for broadband and strong microwave absorption

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Science China(Technological Sciences) 2023年第12期66卷 3574-3584页

作者： duan YuBing liANG QingXuan YANG Zhen WANG xin liU Pan li DiChen School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China

Microwave absorbers(MAs)with broadband and strong microwave absorption capacities are urgently required to meet the demands of complex electromagnetic(EM)***,a novel labyrinth multiresonant metastructure composed of a polyether-ether-ketone/flaky carbonyl iron(PEEK/CIP)magnetic composite was proposed and fabricated via 3D printing technology.A complex multiresonant cavity design was introduced,and the resonant loss area was significantly *** broadband and high-efficiency microwave absorption performances were *** multilayer labyrinth multiresonant metastructure was designed with gradient *** effects of structural parameters on the absorbing properties were investigated and *** and simulations demonstrated the effectiveness of the design *** designed metastructure with a 10 mm thickness exhibited a-10 dB absorption bandwidth at a frequency of 3.78–40 GHz and an absorption bandwidth below-15 dB at 7.5–36.5 ***,an excellent wide-angle absorption performance was observed for different polarization states,including transverse electric(TE)and transverse magnetic(TM)*** combination of a complex multiresonant metastructure design and 3D printing fabrication provides a facile route to considerably extend the absorption bandwidth and strength of electromagnetic *** work is expected to provide a promising strategy for further enhancing microwave absorption performance,and the designed metastructure possesses great application potential in stealth and electromagnetic compatibility technologies.

关键词： labyrinth metastructure multiresonant magnetic composite materials broadband and strong absorption 3D printing