检索结果-南通市图书馆

Numerical Simulation for Refraction-Diffraction of Waves in Water of Slowly Varying Current and Topography

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 1997年第4期12卷 373-386页

作者： Hong, GW Feng, WB Xia, QY Pan, SH Hohai Univ Res Inst Coastal & Ocean Engn Nanjing 210024 Peoples R China

A new numerical finite difference iteration method for refraction-diffraction of waves ia water of slowly varying current and topography is developed in this paper. And corresponding theoretical model including the dissipation term is briefly described, together with some analysis and comparison of computational results of the model with measurements in a hydraulic scale model (Berkhoff et al., 1982). An example of practical use of the method is given, showing that the present model is useful to engineering practice.

关键词： refraction-diffraction of waves on current wave number conservation wave action conservation Eikonal equation time dependent mild slope equation on current energy dissipation

Dispersion of multiwalled carbon nanotubes in aluminum powders

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2009年第2期28卷 175-180页

作者： Deng Chunfeng Zhang Peng Ma Yanxia Zhang Xuexi Wang Dezun Luoyan Ship Mat res inst Luoyan 471039 Peoples R China Harbin inst Technol Sch Mat Sci & Engn Harbin 150001 Peoples R China Harbin inst Technol Sch Mat Sci & Engn Weihai 264209 Peoples R China

Multiwalled carbon nanotubes (MWNTs) were treated with the reflux within the concentrated nitric acid for 0-25 h to purify and disperse the tangled MWNTs. The effect of reflux time on the morphology and the weight loss of MWNTs were investigated. Meanwhile,the dispersion of MWNTs with 0-2.0 wt.% in 2024Al powders using mechanical stirring with an assisting ultrasonic shaker in ethanol was also studied. The results show that the reflux time markedly affects the morphology of MWNTs. The weight loss of MWNTs i...

关键词： metal matrix composite powder processing reflux treatment carbon nanotubes (CNTs)

A new type numerical model for action balance equation in simulating nearshore waves

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2001年第11期46卷 963-968页

作者： Yan, YX Xu, FM Mao, LH Hohai Univ Res Inst Coastal & Ocean Engn Nanjing 210098 Peoples R China

Several current used wave numerical models are briefly described, the computing techniques of the source terms, numerical wave generation and boundary conditions in the action balance equation model are discussed. Not only the quadruplet wave-wave interactions, but also the triad wave-wave interactions are included in the model, so that nearshore waves could be simulated reasonably. The model is compared with the Boussinesq equation and the mild slope equation. The model is applied to calculating the distributions of wave height and wave period field in the Haian Bay area and to simulating the influences of the unsteady current and water level variation on the wave field. Finally, the developing tendency of the model is discussed.

关键词： action balance equation numerical generating waves quadruplet wave-wave interactions triad wave-wave interactions Boussinesq equation mild slope equation.

The Surface Profile of Laser Peening with Square Spots

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 240-242页

作者： Zou S K1,2,Cao Z W1,Che Z G1,Li B21National Key Laboratory for Power Beam Processing Technologies,Beijing Aeronautical Manufacturing Technology research institute,Bei-jing 100024,China2Schoool of mechanical of Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China Beijing Aeronaut Mfg Technol res inst Natl Key Lab Power Beam Proc Technol Beijing 100024 Peoples R China Huazhong Univ Sci & Technol Sch Mech Sci & Engn Wuhan 430074 Peoples R China

The surface profile of laser peened stainless steel was researched in this paper,a special lens was used to convert circle laser spot to square spot,the difference of surface profile obtained by laser peening with circle laser spot was compared with that with square laser *** peened zone showed steep depression at the edge with square spot,but the surface in the shocked zone was very *** suitable overlapped rate,square spot can produce smoother surface profile than circle spot,and laser peening with square spot is more effective than circle spot.

关键词： laser peening surface profile residual stress square spot

Study on the J-Integral and Failure Assessment Line of Electron Beam Welded Thick TC4-DT Alloy Joints

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 58-62页

作者： Lu Wei1,Shi Yaowu1,Li Xiaoyan1,Lei Yongping1,Gong Shuili2,Guan Qiao2,Zhao Haiyan3 1 College of Materials Science and Engineering,Beijing University of Technology,Beijing 100124,China2 Science and Technology on Power Beam Processes Laboratory,Beijing Aeronautical Manufacturing Technology research institute,Beijing 100124,China3 Dept of mechanical Engineering,Tsinghua University,Beijing 100084,China Beijing Univ Technol Coll Mat Sci & Engn Beijing 100124 Peoples R China Beijing Aeronaut Mfg Technol res inst Sci & Technol Power Beam Proc Lab Beijing 100124 Peoples R China Tsinghua Univ Dept Mech Engn Beijing 100084 Peoples R China

The effects of strength mis-matching on J-integral and failure assessment line (FAL) of electron beam welded thick TC4-DT titanium alloy joints have been *** and elastic-plastic finite elements (FE) calculations on centre crack tensile (CCT) specimens were made,and the condition of 20% strength mis-matching was *** results indicate that the limit load of the joint can be substituted by that of the base *** error of substitution is less than 5%.The failure assessment lines for both over-matching and under-matching joints are increasingly close to that of the base metal,with the ratio of weld width to specimen width (H/W) ***,the failure assessment lines of the joints can be devised using the stress-strain curves of the base metal,which will be convenient for the practical application of engineering

关键词： electron beam welding TC4-DT alloy joints limit load J-integral failure assessment line

NONLINEAR DYNAMIC MODELING AND PERIODIC VIBRATION OF A CANTILEVER BEAM SUBJECTED TO AXIAL MOVEMENT OF BASEMENT

在线全文

学校读者我要写书评

暂无评论

Acta mechanica Solida Sinica 2002年第2期15卷 133-139页

作者： Feng Zhihua Hu Haiyan Nanjing Univ Aeronaut & Astronaut Inst Vibrat Engn Res Nanjing 210016 Peoples R China

Dynamic modeling of a cantilever beam under an axial movement ofits basement is present- ed. The dynamic equation of motion for thecantilever beam is established by using Kane's equation first andthen simplified through the Rayleigh-Ritz method. Compared with oldermodeling method, which lineari- zes the generalized inertia forcesand the generalized active forces, the present modeling takes thecoupled cubic nonlinearities of geometrical and inertial types intoconsideration.

关键词： cantilever beam parametric excitation dynamic modeling nonlinear dynamics

An Analysis on Application and Trend of Low-Alloy Steel in Shipbuilding and Offshore Engineering Industry

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel research(International) 2011年第S1期18卷 827-830页

作者： LI Xin-xin,NA Rong-qing,MENG Zhao-chuang (Dalian Shipbuilding Industry Engineering and research institute,Dalian 116000,Liaoning,China) Dalian Shipbldg Ind engn & res inst Dalian 116000 Liaoning Peoples R China

Since 2003,China shipbuilding industry has stepped into the orbit of fast *** this paper,a brief analysis has been made on application of low-alloy steel in the shipbuilding and offshore engineering industry,and the further requirements on the marine steel plates elaborated in combination with the future development trend in this ***,a reference approach is proposed for potential cooperation between the shipbuilding industry and steel industry.

关键词： low-alloy steel ship and offshore engineering

MICROPOROUS PVDF-HFP-BASED POLYMER MEMBRANES FORMED FROM SUPERCRITICAL CO_2 INDUCED PHASE SEPARATION

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2008年第1期26卷 13-21页

作者： Cao, Jian-hua Zhu, Bao-ku Zuo, Dan-ying Xu, You-yi Li, Ji-ding Zhejiang Univ Inst Polymer Sci Hangzhou 310027 Yuquan Peoples R China Tsinghua Univ Dept Chem Engn Membrane Technol & Engn Res Ctr Beijing 100084 Peoples R China

Microporous poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)membranes following supercritical CO_2 induced phase separation process were prepared using four *** solid electrolytes of PVDF-HFP were formed by microporous PVDF-HFP membranes filled and swollen by a liquid *** effect of the solvents on the morphology and structure,electrolyte absorptions and lithium ionic conductivity of the activated membranes were *** was approved that all the membrane had the similar...

关键词： Poly(vinylidene fluoride-co-hexafluoropropylene) Microporous membrane Conductivity Supercritical CO_2

Shape Character of Fusion-solidification Zone of EBW Joints for Titanium Alloy

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 74-78页

作者： Fu Pengfei1,2,Mao Zhiyong2,Wang Yajun3,Gong Shuili2,Liu Xin2 1School of Materials Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China 2Science and Technology on Power Beam Processes Laboratory,Beijing Aeronautical Manufacturing Technology research institute,Beijing 100024,China3School of mechanical Engineering and Automation,Beijing University of Aeronautics and Astronautics,Beijing 100191,China Beijing Aeronaut Mfg Technol res inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China Huazhong Univ Sci & Technol Sch Mat Sci & Engn Wuhan 430074 Peoples R China Beijing Univ Aeronaut & Astronaut Sch Mech Engn & Automat Beijing 100191 Peoples R China

Shape character of fusion-solidification zone of electron beam welding (EBW) joints was studied for TC4 *** typical shapes of the fusion-solidification zone were gained by appropriate welding *** shapes and dimensions of the fusion-solidification zone of TC4 titanium joints were apparently influenced by processing parameters,focusing state and power density *** on the analyses of processing parameters,focusing state and power density distribution,the integrated parameters of n1 and n2 were put forward,which represented the distribution and intensity of electron beam *** a series of the formulations are developed to predict the shape of fusion-solidification zone by the processing parameters.

关键词： electron beam welding (EBW) titanium alloy fusion-solidification zone mathematical model