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Performance comparison and parametric study on spiral groove gas film face seals

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Science china(Physics,Mechanics & Astronomy) 2004年第z1期47卷 29-36页

作者： LIU Yuchuan, SHEN Xinmin, XU Wanfu & WANG ZhiliState Key Laboratory of Tribology, Tsinghua university, Beijing 100084, china school of Mechanical engineering and Automation, Beijing university of Aeronautics and Astronautics, Beijing 100083, china Lubrication technology Research Center, shenyang Institute of technology, shenyang 110015, china Tsing Hua Univ State Key Lab Tribol Beijing 100084 Peoples R China Beijing Univ Aeronaut & Astronaut Sch Mech Engn & Automat Beijing 100083 Peoples R China shenyang Inst Technol Lubricat Technol Res Ctr Shenyang 110015 Peoples R China

Several spiral groove gas film face seals (SGFS) with different layouts are compared quantitatively to analyze their merits and faults and application behaviors. In addition, a parametric study on downstream mode SGFS is conducted to determine its optimal parameters under certain working conditions. In tne computation of gas film pressure on the face, finite element method (FEM) is applied to adapt to complicated geometrical boundary.

关键词： spiral groove, gas film face seals, parameter study, performance comparison, finite element method.

An improved group search optimizer for mechanical design optimization problems

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Progress in Natural Science:Materials International 2009年第1期19卷 91-97页

作者： Hai Shena,b,c,Yunlong Zhu a,Ben Niu a,b,Q.H.Wu d a Key Laboratory of Industrial Informatics,shenyang Institute of Automation,Chinese Academy of Sciences,shenyang 110016,china b Graduate school of the Chinese Academy of Sciences,Beijing 100049,china c College of Physics Science and technology,shenyang Normal university,shenyang 110034,china d Department of electrical engineering and Electronics,The university of Liverpool,Brownlow Hill,Liverpool,L69 3GJ,UK [a]Key Laboratory of Industrial Informatics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China [b]Graduate School of the Chinese Academy of Sciences Beijing 100049 China [c]College of Physics Science and Technology Shenyang Normal University Shenyang 110034 China [d]Department of Electrical Engineering and Electronics The University of Liverpool Brownlow Hill Liverpool L69 3GJ UK

This paper presents an improved group search optimizer(iGSO) for solving mechanical design optimization *** the proposed algorithm,subpopulations and a co-operation evolutionary strategy were adopted to improve the global search capability and convergence *** iGSO is evaluated on two optimization problems of classical mechanical design:spring and pressure *** experimental results are analyzed in comparison with those reported in the *** results show that iGSO has much better convergence performance and is easier to implement in comparison with other existing evolutionary algorithms.

关键词： Mechanical optimization problem GSO Constrained optimization problem

Surface characteristics of rapidly solidified nickel-based superalloy pow-ders prepared by PREP

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Rare Metals 2003年第4期22卷 309-314页

作者： CHEN Huanming , HU Benfu , and LI Huiying1) school of Materials Science and engineering, university of Science and technology Beijing, Beijing 100083, china2) school of Physics and electrical Information engineering, Ningxia university, Yinchuan 750021, china school of Materials Science and engineering University of Science and Technology Beijing Beijing 100083 Chins

The surface microstructure and the surface segregation of FGH 95 nickel-basedsuperalloy powders prepared through plasma rotating electrode processing (PREP) have beeninvestigated by using SEM and AES. The results indicate that the surface microstructure of powderschanges from dendrite into cellular stricture as the particle size of powders decrease, and thepredominant precipitates solidified on the particle surfaces were identified as MC' type carbidesenriched with Nb and Ti. It was also indicated that along with the depth of particle surfaces, thesegregation layer of S, C and O elements are thick, and that of Ti, Cr elements are thin for largesire powders while they are in reverse for median size particles.

关键词： FGH 95 nickel-based superalloy powders surface characteristics microstructure plasma rotating electrode processing

Numerical Simulation and Experimental Investigation of Springback in U-Channel Forming of Tailor Rolled Blank

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Journal of Iron and Steel Research International 2012年第9期19卷 8-12页

作者： ZHANG Hua-wei 1 , LIU Li-zhong 1 , HU Ping 1 , LIU Xiang-hua 2 ( 1.Faculty of Vehicle engineering and Mechanics , State Key Laboratory of Structural Analysis for Industrial Equipment , Dalian university of technology , Dalian 116024 , Liaoning , china 2.Research Institute of Science and technology , Northeastern university , shenyang 110819 , Liaoning , china ) [a] Faculty of Vehicle engineering and Mechanics State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 Liaoning China [b] Research Institute of Science and technology Northeastern University Shenyang 110819 Liaoning China

In order to grasp the springback rule of TRB ( tailor rolled blank ) parts after forming , the springback behavior of TRB was investigated by integrating such three means as theoretical research , numerical simulation and stamping *** theories of springback were *** stamping and springback processes of annealed 1.2 / 2.0mm TRB , 1.2mm and 2.0mm plates for U-channel were simulated , and the simulation results were compared with the *** results indicate that the springback of TRB falls in between those of the 1.2mm and 2.0mm *** is desirable for the TRB U-channel to have die clearance of 1.1times maximum blank thickness and friction coefficient of about 0.12 , and longer thickness transition zone is *** simulation data demonstrate reasonably good agreement with the experiments.

关键词： tailor rolled blank U-channel springback annealing

Study and Analysis on Naphtha Catalytic Reforming Reactor Simulation

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china Petroleum Processing & Petrochemical technology 2004年第4期6卷 49-56页

作者： Liang Ke min1 Song Yongji2 Pan Shiwei3( 1 school of Petrochemical engineering, shenyang university of technology, Liaoyang 111003 2 Department of Chemical engineering, Beijing Institute of Petrochemical technology, Beijing102617 3 school of Advanced Professional technology, shenyang university of technology,Liaoyang 111003) school of Petrochemical engineering Shenyang University of Technology Liaoyang 111003 China Department of Chemical engineering Beijing Inst. of Petrochem. Technol. Beijing 102617 China Sch. of Adv. Professional technology Shenyang University of Technology Liaoyang 111003 China

A naphtha catalytic reforming unit with four reactors connected in series is analyzed. A physicalmodel is proposed to describe the catalytic reforming radial flow reactor. Kinetics and thermodynamicsequations are selected to describe the naphtha catalytic reforming reaction characteristics based on idealiz-ing the complex naphtha mixture to represent the paraffin, naphthene, and aromatic groups with individualcompounds. The simulation results based on above models agree very well with actual operating data ofprocess unit.

关键词： naphtha catalytic reforming kinetics simulation and analysis

SPALLING MECHANISM OF NITRIDED LAYER OF AUSTENITIC STEEL 4Cr14Ni14W2Mo

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Acta Metallurgica Sinica(English Letters) 1989年第5期2卷 374-376页

作者： SUN Xudong LI Jian Northeast university of technology,shenyang,china Lecturer,Dept.of Materials Science and engineering,Northeast university of technology,shenyang,china

The tendency of spalling of the nitrided layer of the hot rolled austenitic steel 4Cr14Ni14W2Mo exhibits close relation to the nitrided surface orientation relative to the rol- led steel *** is found that the dislocations in the imperfectly recrystalized steel align as parallel dislocation walls in macroscopic extent,and the thickness of the“white sublayer”in the nitrided layer is much larger at the surface which is parallel to the dislocation *** such surface the spalling of the nitrided layer happens often.

关键词： nitriding spalling heat resistant steel

Experimental study of dynamic mechanical properties of reactive powder concrete under high-strain-rate impacts

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Science china(Technological Sciences) 2010年第9期53卷 2435-2449页

作者： JU Yang1,2,LIU HongBin1,SHENG GuoHua1,3 & WANG HuiJie1 1 State Key Laboratory of Coal Resources and Safe Mining,Beijing Key Laboratory of Fracture and Damage Mechanics of Rocks and Concrete,china university of Mining and technology,Beijing 100083,china 2 Department of Mechanical and Manufacturing engineering,university of Calgary,2500 university Drive,AB T2N 1N4,Canada 3 school of Resources and Civil engineering,Northeastern university,shenyang 110004,china 1. State Key Laboratory of Coal Resources and Safe Mining Beijing Key Laboratory of Fracture and Damage Mechanics of Rocks and Concrete China University of Mining and Technology Beijing 100083 China2. Department of Mechanical and Manufacturing Engineering University of Calgary 2500 University Drive AB T2N 1N4 Calgary Canada3. School of Resources and Civil Engineering Northeastern University Shenyang 110004 China

The dynamic mechanical properties of reactive powder concrete subjected to compressive impacts with high strain rates ranging from 10 to 1.1×102 s-1 were investigated by means of SHPB (split-Hopkinson-pressure-bar) tests of the cylindrical specimens with five different steel fiber volumetric *** properties of wave stress transmission,failure,strength,and energy consumption of RPC with varied fiber volumes and impact strain rates were *** influences of impact strain rates and fiber volumes on those properties were characterized as *** general forms of the dynamic stress-strain relationships of RPC were modeled based on the experimental *** investigations indicate that for the plain RPC the stress response is greater than the strain response,showing strong brittle *** RPC with a certain volume of fibers sustains higher strain rate impact and exhibits better deformability as compared with the plain *** a constant fiber fraction,the peak compressive strength,corresponding peak strain and the residual strain of the fiber-reinforced RPC rise by varying amounts when the impact strain rate increases,with the residual strain demonstrating the greatest *** the fiber content makes trivial contribution to improving the residual deformability of RPC when the impact strain rate is *** tests also show that the fiber content affects the peak compressive strength and the peak deformability of RPC in a different *** a constant impact strain rate and the fiber fraction less than 1.75%,the peak compressive strength rises with an increasing fiber *** peak compressive strength tends to decrease as the fiber volume exceeds 1.75%.The corresponding peak strain,however,incessantly rises with the increasing fiber *** total energy Edisp that RPC consumed during the period from the beginning of impacts to the time of residual strains elevates with the fiber volume increment as long as the fiber fraction

关键词： impact reactive powder concrete (RPC) high strain rate dynamic strength energy consumption dynamic stress-strain response

基于VRML的可视化虚拟场景生成工具的研究

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系统仿真学报 2005年第1期17卷 72-74页

作者：魏东黄有群合肥工业大学计算机与信息学院安徽合肥230009 沈阳工业大学信息科学与工程学院辽宁沈阳110023

构造和生成VRML虚拟场景的流行工具和国内的研究多保持在用VRML文本编辑器直接书写程序的方式上,研究通过在场景上的图形操作,非编程地生成VRML场景的实现方法,并开发了一个实用系统。该方法不需要用户了解VRML语法,生成过程方便快捷。

关键词：虚拟场景 VRML 可视化生成工具

Description to wear debris boundaries by radar graph fractal method

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Chinese Science Bulletin 2007年第16期52卷 2285-2290页

作者： LIU HongTao1,2 & GE ShiRong1 1 Institute of Tribology and Reliability engineering,china university of Mining & technology,Xuzhou 221008,china 2 College of Mechanical and electrical engineering,china university of Mining & technology,Xuzhou 221116,china Institute of Tribology and Reliability engineering China University of Mining and Technology Xuzhou 221008 China

In this paper,radar graph fractal method is introduced to describe wear debris boundaries. Research results show that it is a nice way to describe wear debris boundaries. Since the longest axis is selected as the first coordinate axis,its center point selected as the center point of the radar graph,and the co-ordinate value of wear debris boundary selected as the measure parameter,the limitations existing in Yard fractal measure method can be avoided. For any wear debris,its radar graph fractal dimension value is one and only,and as the wear debris shape changes from round to strip,the radar graph fractal dimension value also changes from low to high,showing strong uniqueness and independence. Due to the fact that the researched wear debris is gotten in different wear states,the results also prove that radar graph fractal dimension value is correlated with frictional pairs work condition and wear state. Radar graph fractal method is compared with Yard fractal measure methods,and results show that ra-dar graph fractal dimension values gotten from different wear debris have enough value grads to avoid effect of errors,and provide higher sensitivity for wear debris shape. This paper also discusses the influencing factors for radar graph fractal method. With the increase of the decomposing degree value,the radar graph fractal dimension tends to keep stable at one certain value,showing the typical characteristic of the fractal theory. All this proves that radar graph fractal method is an effective description method for wear debris boundaries.

关键词：磨粒边界雷达图表分形法