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Simulation algorithm for spiral case structure in hydropower station

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Water Science and Engineering 2013年第2期6卷 230-240页

作者： Xin-yong XU zhen-yue MA Hong-zhan ZHANG Faculty of Infrastructure Engineering Dalian University of Technology School of Hydraulic Engineering North China University of Water Resources and Electric Power

In this study, the damage-plasticity model for concrete that was verified by the model experiment was used to calculate the damage to a spiral case structure based on the damage mechanics theory. The concrete structure surrounding the spiral case was simulated with a three-dimensional finite element model. Then, the distribution and evolution of the structural damage were studied. Based on investigation of the change of gap openings between the steel liner and concrete structure, the impact of the non-uniform variation of gaps on the load-beating ratio between the steel liner and concrete structure was analyzed. The comparison of calculated results of the simplified and simulation algorithms shows that the simulation algorithm is a feasible option for the calculation of spiral case structures. In addition, the shell-spring model was introduced for optimization analysis, and the results were reasonable.

关键词： hydraulic structure simulation," concrete damage-plasticity model," shell-springmodel spiral ease

Role of Hydrodynamic Interactions in the Deformation of Star Polymers in Poiseuille Flow

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Chinese Journal of Polymer Science 2020年第4期38卷 363-370,I0006页

作者： zhen-yue Yang Xiao-Fei Tian Li-Jun Liu Ji-Zhong Chen State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Chinese Academy of Sciences Beijing 100049China

Stretching polymer in fluid flow is a vital process for studying and utilizing the physical properties of these molecules,such as DNA linearization in nanofluidic *** studied the role of hydrodynamic interactions(His)in stretching a free star polymer in Poiseuille flow through a tube using mesoscale hydrodynamic *** increasing the flow strength,star polymers migrate toward the centerline of tube due to His,whereas toward the tube wall in the absence of *** analyzing the end monomer distribution and the perturbed flow around the star polymer,we found that the polymer acts like a shield against the flow,leading to additional hydrodynamic drag forces that compress the arm chains in the front of the star center toward the tube axis and lift the arm chai ns at the back toward the tube *** balanced hydrodynamic forces freeze the polymer into a trumpet structure,where the arm chains maintain a steady strongly stretched state at high flow *** contrast,the polymer displays remarkably large conformational change when switching off *** simulation results explained the coupling between His and the structure of star polymers in Poiseuille flow.

关键词： Hydrodynamic interactions Star polymer Poiseuille flow Migration

Effect of Temperature on the Dynamic Recrystallization of AZ31 Alloy with Pulse Current

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Acta Metallurgica Sinica(English Letters) 2018年第12期31卷 1281-1286页

作者： Shu-Xia Lin Xing-Rong Chu zhen-Ming yue Jun Gao School of Mechanical Electrical and Information Engineering Shandong University

The tensile tests of AZ31 magnesium alloy were carried out under room temperature, 100, 150 and 200 ℃ with andwithout pulse current. The effect of temperature on dynamic recrystallization （DRX） of AZ31 alloy was studied at differentconditions. One-parameter approach was used to analyze the critical conditions of DRX, the critical stress was obtainedunder different temperatures, and the related results were validated by metallography observation. The results showed thatDRX of AZ31 alloy occurred at 200 ℃ without pulse current. When pulse current with 150 Hz/50 V parameter wasapplied at room temperature, DRX occurred, while DRX was not completed until temperature over 150 ~C. With theanalysis result of critical conditions of DRX based on one-parameter approach, the relationship between critical stress andpeak stress obtained in this present study is σc = （0.746-0.773）σp.

关键词： AZ31 alloy Electroplasticity Dynamic recrystallization One-parameter approach

Two new C-glucoside oxanthrones from Rumex gmelini

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Chinese Chemical Letters 2009年第7期20卷 839-841页

作者： zhen yue Wang Hai Peng Zhao yue Ming Zuo Zong Quan Wang Xian Ming Tang Graduate School of Heilongjiang University of Traditional Chinese Medicine Harbin 150040 China Lunan Pharmaceutical Group Corporation Linyi 276005 China Jiangxi University of Traditional Chinese Medicine Nanchang 330004 China Yiling Pharmaceutical Group Corporation Shijiazhuang 050035 China Harbin Food and Drug Administration Harbin 150016 China

Two new C-glucoside oxanthrones, 6-methoxyl-10-hydroxyaloin A （1） and 6-methoxyl-10-hydroxyaloin B （2）, were isolated from the roots of Rumex gmelini Turcz. Their structures were elucidated on the basis of spectroscopic techniques and chemical means C 2009 zhen yue Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved.

关键词： Rumex gmelini Turcz. C-glucosidc oxanthrones 6-Methoxyl-10-hydroxyaloin A 6-Methoxyl-10-hydroxyaloin B

Application of numerical simulation to flow induced corrosion in flowing seawater system

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中国有色金属学会会刊：英文版 2004年第z1期14卷 439-442页

作者： LIU Jing-jun LIN Yu-zhen YONG Xing-yue LI Xiao-yu School of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China School of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China School of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China School of Materials Science and Engineering Beijing University of Chemical Technology Beijing 100029 China

An established model was presented as a new kind of means for investigating flow induced corrosion. In this method the near-wall hydrodynamic parameters including wall shear stress τ and mass transfer coefficient k near the wall of materials can be numerically calculated, and combining corrosive kinetics tested by experiments, the corrosion rates can be also calculated accurately. The flow induced corrosion mechanism was further verified by numerical results in this model, and the various corrosion phenomena were explained. The modelled results also show that the ability to accurately utilize numerical method to study flow induced corrosion strongly to some extent depends on material corrosive kinetics processes tested by experiments.

关键词： flow induced corrosion numerical simulation near-wall hydrodynamic parameters mechanism

维普期刊数据库评论

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氟碳铈矿浮选捕收剂及作用机理研究进展

稀土 2024年第4期45卷 1-10页

作者：张臻悦杨静郭文达蒋灵刘德峰池汝安武汉工程大学兴发矿业学院湖北武汉430073 绿色化工过程教育部重点实验室湖北武汉430073 湖北兴发化工集团有限公司湖北宜昌443000

氟碳铈矿作为分布广泛、储量最多、工业价值较高的稀土矿物,氟碳铈矿高效浮选理论和工艺的研究对于提高稀土资源利用率、加快相关领域发展具有重要战略意义。本文针对目前氟碳铈矿浮选捕收剂种类繁多,捕收剂在氟碳铈矿表面作用机理和氟... 详细信息

氟碳铈矿作为分布广泛、储量最多、工业价值较高的稀土矿物,氟碳铈矿高效浮选理论和工艺的研究对于提高稀土资源利用率、加快相关领域发展具有重要战略意义。本文针对目前氟碳铈矿浮选捕收剂种类繁多,捕收剂在氟碳铈矿表面作用机理和氟碳铈矿选择性分离机制研究缺乏系统性概述的问题,对氟碳铈矿浮选捕收剂进行分类总结,分析氟碳铈矿捕收剂作用机理,展望未来氟碳铈矿浮选捕收剂的研究方向,以期为氟碳铈矿浮选行为研究和浮选药剂的开发提供有益的参考和指导,助力氟碳铈矿的高效回收利用。

关键词：氟碳铈矿浮选捕收剂作用机理分离特性

Experimental Investigation on Formability of AZ31B Magnesium Alloy V-Bending Under Pulse Current

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Acta Metallurgica Sinica(English Letters) 2018年第12期31卷 1249-1257页

作者： Xing-Rong Chu Lei Wang Shu-Xia Lin zhen-Ming yue Jun Gao Associated Engineering Research Center of Mechanics and Mechatronic Equipment Shandong University Weifang GeorTek Electronics Co. Ltd.

In this work, the influence of pulse current parameters on springback and bending force of magnesium alloy duringelectropulse-assisted （EPA） V-bending was investigated. The experimental results showed that pulse current can effec-tively reduce the springback and the bending force compared to the experiments without current. The frequency has a moresignificant influence on bending force and springback than electric current density. Electroplastic （EP） effect begins towork when pulse current parameters reach a threshold value. To explore the mechanism of EPA V-bending, themicrostructure evolution and fracture surface of the bending specimen were studied. It was found that pulse current canpromote the occurrence of dynamic recrystallization （DRX） of magnesium alloy compared to traditional hot formingprocess. The fracture mode of AZ31B under EPA V-bending evolves from brittle fracture to ductile fracture withincreasing pulse current parameters. Based on the discussion of athermal and thermal effects of EP effect, the mechanismof pulse current to promote DRX is studied and athermal effect is proved to exist.

关键词： AZ31B alloy Pulse current Electroplastic (EP) effect Springback Dynamic recrystallization

A Service Relevance Based Matching Algorithm on Grid Environment

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 269-272页

作者： QIN Wen-yan XU Li-zhen HE Jie-yue Department of Computer Science and Engineering Southeast University Nanjing 210096 Jiangsu China

This paper presents a semantic metadata description model for grid services, and furthermore, a service relevance based matching algorithm is proposed. Some rea sonable parameters interpreting services characterizations are considered to advise matching process, whose weightiness and service relevance dramatically contribute to the decision making of service matching degree, And what＇s more, matching is secondly executed on the bases of experience adaptation of matching factors, which improves matching degree in gird service retrieve greatly.

关键词： grid ontology semantic metadata service relevance match

Numerical study of influence of J×B force on melt layer under conditions relevant to ITER ELMs

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Chinese Physics B 2019年第4期28卷 254-260页

作者： Yan Huang Ji-Zhong Sun Juan Cai zhen-yue Sun Chao-Feng Sang De-zhen Wang School of Information Science and Engineering Dalian Polytechnic University Key Laboratory of Materials Modification by Laser Ion and Electron Beams (Ministry of Education)School of Physics Dalian University of Technology School of Physics and Electronic Technology Liaoning Normal University

The influence of the J×B force on the topographical modification of W targets during a type-I-like ELM in ITER has been studied numerically. A two-dimensional(2D) fluid dynamics model is employed by solving liquid hydrodynamic Navier-Stokes equation with the 2D heat conduction equation in addition to driving forces for surface topography, such as surface tension and pressure gradient, the J×B force is particularly addressed. The governing equations are solved with the finite volume method by adequate prediction of the moving solid-liquid interface. Numerical simulations are carried out for a range of type-I ELM characteristic parameters. Our results indicate that both the surface tension and the J×B force contributes to the melt motion of tungsten plates when the energy flux is under 3000 MW·m^(-2), the surface tension is a major driving force while the pressure gradient is negligible. Our results also indicate that the J×B force makes the small hills grow at different rates at both the crater edges under a type-I-like ELM heat load with a Gaussian power density profile.

关键词： ELMs tungsten divertor plates J×B force melt motion