检索结果-南通市图书馆

A MICROSTRUCTURE-BASED ANALYSIS FOR CYCLIC PLASTICITY OF DUAL-PHASE PEARLITIC RAIL STEELS

在线全文

学校读者我要写书评

暂无评论

Acta mechanica Solida Sinica 2001年第4期14卷 334-343页

作者： Peng Xianghe Chang Jian Chongqing Univ Dept Engn Mech Chongqing 400044 Peoples R China

Based on the assumption that a representative element of apearlitic steel is an aggregate of numerous spherical pearliticcolonies with randomly distributed orientations, and that each colonyis com- posed of many parallel fine lamellas of ferrite andcementite, a description for the dual-phase pearlitic steel isobtained by making use of a microstructure-based constitutiveequation for a single dual-phase pearlitic colony and the Hill'sself-consistent scheme. The elastoplastic response of dual-phasepearlitic steel BS11 subjected to asymmetrically cyclic loading isanalyzed, and a comparison with the experimental results showssatisfacto- ry agreement. The non-proportional cyclic plasticity ofBS11 is also analyzed, in which stress develops along a semi-circlein a biaxial tension/compression and shear stress plane, as istypically experienced by the sur- face elements in rolling andsliding contact.

关键词： pearlitic steel lamellar dual-phase material Hill's self-consistent scheme cyclic plasticity

APPLICATION OF THE DUAL RECIPROCITY BOUNDARY ELEMENT METHOD TO SOLUTION OF NONLINEAR DIFFERENTIAL EQUATION

在线全文

学校读者我要写书评

暂无评论

Acta mechanica Solida Sinica 2000年第2期13卷 173-178页

作者： Long, SY Zhang, Q Hunan Univ Dept Mech Engn Changsha 410082 Peoples R China

In this paper the dual reciprocity boundary element method is employed to solve nonlinear differential equation del(2) u + u + epsilon u(3) = b. Results obtained in an example have a good agreement with those by FEM and show the applicability and simplicity of dual reciprocity method (DRM) in solving nonlinear differential equations.

关键词： the dual reciprocity boundary element method nonlinear differential equation

THE 3-D BOUNDARY ELEMENT METHOD OF ROLLER BEARING BY PLATE ELEMENT ANALOGUE

在线全文

学校读者我要写书评

暂无评论

Acta mechanica Solida Sinica 2001年第3期14卷 268-274页

作者： Shen Guangxian Shu xuedao Li Ming Yanshan Univ Dept Mech Engn Qinhuangdao 066004 Peoples R China

The mill roller bearing is made up of an internal ring, middlerolls and an external ring, the analysis of which is a multi-bodiescontact problem. In this paper, based on the three-dimensionalelastic contact BEM without friction, and using the structuralcharacteristics of roller bearings, middle rolls are de- scribed byelastic plate units of different shapes, which is placed on theinternal ring.

关键词： roller bearing traction sub-element method elastic plate element

NONLINEAR VIBRATION OF BEAMPLATES WITH A DELAMINATION

在线全文

学校读者我要写书评

暂无评论

Acta mechanica Solida Sinica 2000年第4期13卷 353-362页

作者： Fu Yiming Zhang Yunliang Hunan Univ Dept Engn Mech Changsha 410082 Peoples R China

The problem of beam-plates with a delamination located at anarbitrary site undergoing non- linear free vibration without damp isinvestigated. For this problem, nonlinear governing equations as wellas the continuity, equilibrium and compatibility conditions areestablished. The Galerkin method and harmonic balance method areemployed to find solutions. Finally, in some examples,amplitude-frequency curves of the delaminated structure are presentedin order to reveal some special dynamic features.

关键词： delamination beam-plate nonlinear vibration

Ultrasonic Frequency Fast-Convert Pulse Plasma Spraying Power Supply Topology

在线全文

学校读者我要写书评

暂无评论

稀有金属材料与工程 2011年第S4期40卷 297-301页

作者： Zhang Wei1,Qi Bojin1,Xu Haiying21School of mechanical Engineering and Automation,BeiHang University,Beijing 100191,China2Beijing Aeronautical Manufacturing Technology Research institute,Beijing 100024,China BeiHang Univ Sch Mech Engn & Automat Beijing 1000191 Peoples R China Beijing Aeronaut Mfg Technol Res inst Beijing 100024 Peoples R China

Considering the high DC current and high pulse frequency characteristic of ultrasonic frequency fast-convert pulse plasma spraying process,a special power supply topology was proposed,which was composed of the mutual independent base current circuit and peak current *** current circuit was consisted of four parallel direct current power supplies,which was not only to meet the requirements of high power output,but also improved the reliability of power *** on the Boost circuit topology,a peak current circuit was designed,which could reduce effectively the output inductance influence and output ultrasonic frequency pulse high current with fast-convert rising and falling *** on the above techniques,the Ultrasonic frequency fast-convert pulse plasma spraying power supply was *** can output 5-1000A base current,0-250A peak current,and the pulse current frequency band is 20-100kHz,10%～80% duty ratio and pulse current change rate over 50A/μs.

关键词： Ultrasonic frequency pulse Fast-convert Plasma spraying

PREPARATION　AND　PROPERTIES　OF　RARE　EARTH　HYDROXIDES　AND　OXIDES　ULTRAFINE　POWDERS　IN　ALCOHOL

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 1995年第11期6卷 1017-1020页

作者： Dong, XT Liu, ZR Yang, KS Liu, JH Hong, GY Yu, DC Changchun inst Opt & Fine mech Dept Mat Engn Changchun 130022 Peoples R China Acad Sinica Changchun Inst Appl Chem Changchun 130022 Peoples R China

A series of rare earth hydroxides and oxides ultrafine powders have been prepared by precipitation method using alcohol as dispersive and proteclive reagent. It was first to find that the crystallite size of cubic rare earth oxides had lanthanide shrinking effect, but average crystal lattice distortion rate possessed lanthanide swelling effect; the change of diffraction intensity with atomic number presented an inverted W type, and double peaks structure was formed.

关键词：

ANALYSIS OF DISSIPATIVE STRUCTURE IN MATERIAL COMMINUTION

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 1995年第1期5卷 21-24,41页

作者： Zhang Zhitie(Department of mechanical Engineering, Central South University of Technology, Changsha 410083) CENT S UNIV TECHNOL DEPT MECH ENGNCHANGSHA 410083PEOPLES R CHINA

ＡＮＡＬＹＳＩＳＯＦＤＩＳＳＩＰＡＴＩＶＥＳＴＲＵＣＴＵＲＥＩＮＭＡＴＥＲＩＡＬ　ＣＯＭＭＩＮＵＴＩＯＮＺｈａｎｇ；Ｚｈｉｔｉｅ（ＤｅｐａｒｔｍｅｎｔｏｆＭｅｃｈａｎｉｃａｌＥｎｇｉｎｅｅｒｉｎｇ，ＣｅｎｔｒａｌＳｏ... 详细信息

ＡＮＡＬＹＳＩＳＯＦＤＩＳＳＩＰＡＴＩＶＥＳＴＲＵＣＴＵＲＥＩＮＭＡＴＥＲＩＡＬ　ＣＯＭＭＩＮＵＴＩＯＮＺｈａｎｇ；Ｚｈｉｔｉｅ（ＤｅｐａｒｔｍｅｎｔｏｆＭｅｃｈａｎｉｃａｌＥｎｇｉｎｅｅｒｉｎｇ，ＣｅｎｔｒａｌＳｏｕｔｈＵｎｉｖｅｒｓｉｔｙｏｆＴｅ...

关键词： material comminution dissipative structure catastrophe nonlinear thermodynamics dynamics

Simulation of quenching in horizontal geometry channel

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2010年第6期21卷 370-374页

作者： Yuan Jingtian Tong Lili Cao Xuewu Shanghai Jiao Tong Univ Sch Mech Engn Shanghai 200240 Peoples R China

Two tests of refilling and reflooding in the horizontal geometry channel under different pressure conditions,respectively,are conducted to understand the thermal hydraulics behavior during a LOCA in the CANDU *** case of refilling a hot horizontal tube test and four cases of reflooding a horizontal fuel channel test series (35%and 60%break size of reactor inlet header with single-end injection or both-end injection,respectively) have been *** horizontal channel is simulated with the model splitting as parallel pipes with cross flow junction *** simulation results have been compared with the tests in terms of wall temperature or heated-pin surface *** results are reasonably acceptable and it shows that the code is applicable on horizontal channel quenching.

关键词：水平测试通道测试模型模拟几何淬火 CANDU堆压力条件热工水力

OPTIMAL CONTROL OF STRETCHING PROCESS OF SOLAR ARRAYS ON SPACECRAFT USING WAVELET EXPANSION METHOD

在线全文

学校读者我要写书评

暂无评论

Acta mechanica Solida Sinica 1998年第4期11卷 351-358页

作者： Ge, XS Zhang, QZ Liu, YZ Beijing inst Machinery Ind Beijing 100085 Peoples R China Shanghai Jiao Tong Univ Dept Engn Mech Shanghai 200030 Peoples R China

The optimal attitude control problem of spacecraft during its solar arrays stretching process is discussed in the present paper. By using the theory of wavelet analysis in control algorithm, the discrete orthonormal wavelet function is introduced into: the optimal control problem, the method of wavelet expansion is substituted for the classical Fourier basic function. An optimal control algorithm based on wavelet analysis is proposed. The effectiveness of the wavelet expansion approach is shown by numerical simulation.

关键词： spacecraft optimal control solar arrays stretching wavelet expansion