检索结果-南通市图书馆

An Expert System in FRP Composite Material Design

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2001年第5期17卷 556-560页

作者： Qingfen LI, Zhaoxia CUI and Weimin WANG College of mech.nical & Electrical eng.neering, Harbin eng.neering University, Harbin 150001, China Jianhua GAO Department of mech.nical eng.neering, Shanghai Jiao Tong University, Shanghai 200030, China Coll. of mech. and electron. eng. Harbin Eng. Univ. Harbin 150001 China

An expert system prototype for fibre-reinforced plastic matrix (FRP) composite material design, ESFRP, has been developed. The system consists of seven main functional parts: a general inference eng.ne, a set of knowledge bases, a material properties algorithm base, an explanation eng.ne, various data bases, several function models and the user interface. The ESFRP can simulate human experts to make design sch.me for fibre-reinforced plastics design, FRP layered plates design and FRP typical eng.neering components design. It can also predict the material properties and make streng.h analysis according to the micro and macro mech.nics of composite materials. A satisfied result can be gained through the reiterative design.

关键词： An Expert System in FRP Composite Material Design FRP

Superplasticity of a SiCw/Zn-22Al Composites

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2004年第2期20卷 172-174页

作者： Xiaojing XU, Wei WANG and Lan CAIsch.ol of mech.nical eng.neering, Jiangsu University, Zhenjiang 212013, China sch. of mech. eng. Jiangsu Univ. Zhenjiang 212013 China

In this paper, the superplastic characteristics of a 15 SiC(vol. pct) whisker reinforced Zn-22AI alloy composites, fabricated by low pressure infiltration and solute treatment after extrusion with the extrusion rate of 10:1, was investigated. The result showed that the composite exhibited a tensile elongation of 150% and a strain rate sensitivity value of about 0.33 at the initial strain rate of 6.67×10-2 s-1 and at 658 K where an appropriate amount of liquid phase was presented in the composite.

关键词： Superplasticity SiCw/Zn-22Al matrix composite Liquid phase

BREAKING WAVE FORCES ON VERTICAL CYLINDERS

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2002年第4期14卷 110-112页

作者： Ma Ru-jian, Li Gui-xi Department of mech.nical and electron.c eng.neering, Jinan University, Jinan 250022, China Dept. of mech. and electron. eng. Jinan Univ. Ji'nan 250022 China

The breaking wave forces on vertical cylinders in shallow waters were studied by means of experimental methods. The results indicate that the breaking wave pressure is distributed exponentially with respect to water depth. An experimental formula was given using the test data. Compared with test data, the calculated breaking wave forces are in good agreement with the test data.

关键词： breaking wave forces pressure distribution of breaking waves experimental study

Low-temperature chemistry in plasma-driven ammonia oxidative pyrolysis

在线全文

学校读者我要写书评

暂无评论

GREEN ENERGY & ENVIRONMENT 2024年第9期9卷 1477-1488页

作者： Zhang, Mingming Chen, Qi Zhou, Guangzhao Sun, Jintao Lin, He Beijing Jiaotong Univ Sch Mech Elect & Control Engn Beijing 100044 Peoples R China Shanghai Jiao Tong Univ Sch Mech Engn Shanghai 200240 Peoples R China

Ammonia is gaining increasing attention as a green alternative fuel for achieving large-scale carbon emission reduction. Despite its potential technical prospects, the harsh ignition conditions and slow flame propagation speed of ammonia pose significant challeng.s to its application in eng.nes. Non-equilibrium plasma has been identified as a promising method, but current research on plasma-enhanced ammonia combustion is limited and primarily focuses on ignition characteristics revealed by kinetic models. In this study, low-temperature and low-pressure chemistry in plasma-assisted ammonia oxidative pyrolysis is investigated by integrated studies of steady-state GC measurements and mathematical simulation. The detailed kinetic mech.nism of NH3 decomposition in plasma-driven Ar/NH3 and Ar/NH3/O2 mixtures has been developed. The numerical model has good agreements with the experimental measurements in NH3/O2 consumption and N2/H2 generation, which demonstrates the rationality of modelling. Based on the modelling results, species density profiles, path flux and sensitivity analysis for the key plasmaproduced species such as NH2, NH, H2, OH, H, O, O(1D), O2(a1Dg), O2(b1Sg+), Ar*, H , Ar+, NH3+, O2 in the disch.rge and afterglow are analyzed in detail to illustrate the effectiveness of the active species on NH3 excitation and decomposition at low temperature and relatively higher E/N values. The results revealed that NH2, NH, H as well as H2 are primarily generated through the electron.collision reactions e + NH3 - e + NH2 + H, e + NH3 - e + NH + H2 and the excited-argon collision reaction Ar* + NH3 + H - Ar + NH2 + 2H, which will then react with highly reactive oxidative species such as O2*, O*, O, OH, and O2 to produce stable products of NOx and H2O. NH3 - NH is found a specific pathway for NH3 consumption with plasma assistance, which further highlights the enhanced kinetic effects. (c) 2024 Institute of Process eng.neering, Chinese Academy of Sciences. Publishing serv

关键词： Non-equilibrium plasma Ammonia fuel Oxidative pyrolysis Pathway flux analysis Sensitivity analysis HYBRID REPETITIVE NANOSECOND ATMOSPHERIC-PRESSURE ARC-DIsch.RGE EXCITATION REDUCTION METHANE AIR

Calculations of Forming Limit Diagrams for Changing Strain Paths on the Formability of Sheet Metal

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2001年第1期17卷 141-142页

作者： Hyunsung Sou Graduate sch.ol of mech.nical eng., Kyungpook National University, Korea Youngsuk Kim Dept. of mech.nical eng., Kyungpook National University, Korea Graduate sch. of mech. eng. Kyungpook Natl. Univ. Kyungpook South Korea

In the press shop of most sheet metals, sheet material undergoes complex strain path and also the formability of the sheet material was limited by the stretchability of the material. Therefore, the precise prediction of path-dependent FLD based on M-K approach using generalization of Hill's 1979 anisotropic yield criterion and introducing a strain gradient effect in the constitutive equation. Also, the theoretically obtained FLD will be compared with experimental data for steel sheets.

关键词： Sheet Metal sheet material strain gradient effect constitutive equation experimental data yield criterion steel sheets strain path

Improvement on strip flatness of cold temper mills by modifying roll contour shape

在线全文

学校读者我要写书评

暂无评论

Journal of University of Science and Technology Beijing 2004年第3期11卷 251-255页

作者： Xiaoyan Li Jie Zhang Xianlin Chen Jianguo Cao Haixia Li mech.nical eng.neering sch.ol, University of Science and Technology Beijing, Beijing 100083, China mech. eng. sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

A study on roll gap profile (strip profile) control was accomplished in a1700 mm single-stand temper mill. Some critical problems such as the deviation of work roll contourcaused by grinding and wear, the effectiveness of work roll bending were discussed. Using a finiteelement model, the effects of roll contours (ground and wear) on strip profile were *** roll bending effect on strip thickness was also analyzed. It is pointed out that there are somespecial features of flatness control in the temper mill: during temper rolling, roll deformation isslight due to small rolling load, and the loaded roll gap profile mainly depends on work rollcontour, while the backup roll has a little effect on gap crown; the effect of bending force ongauge can not be ignored due to the coupling between flatness control and gauge control. A new rollcontour arrangement adaptable to the mill was presented and has been put into practical *** application of the new set of rolls showed some good results: larger crown control range of workroll bender, higher rolling stability, better strip profile and flatness quality.

关键词： cold rolling temper mill strip shape control roll contour arrangement bending

Metal deformation in skew rolling step-shaft

在线全文

学校读者我要写书评

暂无评论

Journal of University of Science and Technology Beijing 2003年第5期10卷 59-63页

作者： Yongqiang Kang, Jinping Liu, Cuiping Yang, and Zheng.uan Humech.nical eng.neering sch.ol, University of Science and Technology Beijing, Beijing 100083, China mech. eng. sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The process of rolling step-shaft was simulated with the help of the FEM(Finite-Element Model) software-DEFORM^(TM) 3D. The characteristics of metal flow in differentperiods were analyzed, and the curve of variety in non-round area at different cross-sections of therolled piece, the curve of variety in bulge volume and the curve of variety in non-column volumewere obtained. On this base the method of tool design is worked out and validated by experiment.

关键词： skew rolling FEM metal deformation non-column volume bulge volume

Three-Dimensional Rigid-Plastic FEM Simulation of Bulk Forming Processes with New Contact and Remeshing Techniques

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2001年第3期17卷 329-332页

作者： Debin Shan and Youngsuk Kim sch.ol of mech.nical eng.neering, Kyungpook National University, Taegu 702-70 1, South Korea Hyunsoo Kim Graduate sch.ol of mech.nical eng.neering, Kyungpook National University, Taegu 702-701, South Korea E-mail: shandb@public sch. of mech. eng. Kyungpook Natl. Univ. Taegu 702-701 South Korea

Some techniques such as die surface description, contact judgement algorithm and remeshing are proposed to improve the robustness of the numerical solution. Based on these techniques, a three-dimensional rigid-plastic FEM code has been developed. Isothermal forging process of a cylindrical housing has been simulated. The simulation results show that the given techniques and the FEM code are reasonable and feasible for three-dimensional bulk forming processes.

关键词： Three-Dimensional Rigid-Plastic FEM Simulation of Bulk Forming Processes with New Contact and Remeshing Techniques FEM Simulation

Numerical Analysis of Hydroforming Deep Drawing of Conical Cup

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2001年第1期17卷 131-132页

作者： Yongming KONG Xianbin ZHOU and Min LI Research Center of Sheet Metal Forming, sch.ol of mech.nical eng.neering & Automation, Beijing University of Aeronautics & Astronautics, Beijing 100083, China sch. of mech. eng. Beijing Univ. of Aeron. and Astron. Beijing 100083 China

Aided by the FE-code. analysis is carried to find the proper hydroforming deep-drawing condition for the perfect forming of a conical cup that can not be drawn successfully by conventional deep drawing method. Hydraulic counter pressure must be reasonably controlled, otherwise defects such as fracture and wrinkling can not be avoided. Therefore, the forming procedure is divided into three stages, and the counter pressure is adjusted intentionally to make the blank clamped onto the punch at a suitable time, then deformation at dangerous area is resisted by the effect of the counter pressure and the conical cup can be formed without defects.

关键词： Numerical Analysis of Hydroforming Deep Drawing of Conical Cup Figure