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Exp.r.mental study of rock-breaking with an offset single cone bit

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petroleum Science 2008年第2期5卷 179-182页

作者： Chen Yinghua school of mechanical and Electronic engineering China University of Petroleum Beijing 102249 China

An exp.r.mental study of rock-breaking with an offset single cone bit was completed on the bit bench test equipment. Data such as transmission ratio, weight on bit （WOB）, rate of penetration （rOp） and torque on bit were acquired in the exp.r.ments. Based on analyzing the exp.r.mental results, several conclusions were drawn as follows. The transmission ratio of the offset single-cone bit changed slightly with rotary speed of bit, weight on bit and offset distance. The rate of penetration of the offset singlecone bit increased with increase of WOB and off＇set distance. The torque on bit increased with increase of offset distance under the same WOB and bit rotary speed, decreased with increase of bit rotary speed under the same WOB. The rock-breaking mechanism of the offset single-cone bit was a scraping action. This indicates that the offset single-cone bit is a chipping type bit.

关键词： Offset single-cone bit transmission ratio rate of penetration torque on bit

Digital Kilns and Furnaces——the Development Direction of Industrial Kilns and Furnaces in the 21st Century

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武汉理工大学学报 2006年第S1期28卷 260-264页

作者： WANG Xiaoming,HUANG Zhichu,ZHANG Jiafan (school of mechanical and electrical engineering,Wuhan University of Technology, Wuhan 430070,china) school of mechanical and electrical engineering Wuhan University of TechnologyWuhan 430070China

The digital manufacturing theory is applied to the special manufacturing equipments——industrial kilns and furnaces; the concept of digital kilns & furnaces is put forward. The present status of research and application for digital technologies in fuel industrial kilns & furnaces is also introduced. Then,take the case of gas fuel kilns & furnaces,their main key technical issues are discussed. Digital kilns & furnaces as an imp.r.ant constituent of the digital equipments are the crucial base of the digital manufacturing. The value of research on digital kilns & furnaces and the application prospect are undoubted. It will improve product quality,reduce the manpower cost,enhance product market competitive ability,promote comprehensively tradition industries such as ceramics,metallurgy industry,and so on.

关键词： digital manufacturing digital equipment digital kilns and furnaces digital technologies

Sol-gel-derived Hybrid Conductive Films for Electromagnetic Interference (EMI) Shielding

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Journal of Wuhan University of Technology(Materials Science) 2011年第2期26卷 217-222页

作者：解基源 school of Information and Comunication engineering North University or China

The conductive nano-sized zinc p.r.icles were embedded in an insulating amorphous silica matrix,and the hybrid films were obtained by a sol-gel *** stable hybrid sol solution was prep.r.d by hydrolysis and condensation of Methyltrimethoxysilane （MTMS） with a one-step acidic catalyst *** films were dip-coated on silicon wafer and cured at 120℃ for *** structural characterization of hybrid films were investigated by means of attenuated total reflection infrared （ATr-Ir） spectroscopy and X-ray diffraction （XrD）.The electrical prop.r.ies of the films were examined with four-point *** films showed to be relatively dense,uniform and defect *** conductivity of hybrid films was varied with the different contents of zinc nanop.r.icles and the thickness of the *** was observed that there was the p.r.olation threshold for the film＇s electrical prop.r.ies.

关键词： sol-gel hybrid films conductive EMI shielding

Flow visualization of silicon-based micro pulsating heat pipes

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Science china(Technological Sciences) 2010年第4期53卷 984-990页

作者： QU Jian & WU HuiYing Key Laboratory for power Machinery and engineering of Ministry of Education,school of mechanical engineering,Shanghai Jiaotong University,Shanghai 200240,china 1. Key Laboratory for power Machinery and engineering of Ministry of Education School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200240 China

Two sets of silicon-based micro pulsating heat pipes(SMpHps) with trapezoidal cross section having hydraulic diameters of 352 μm(#1) and 394 μm(#2) respectively were fabricated for the first time using MEMS *** FC-72 as the working fluid,the start-up,steady op.r.tion state,as well as flow patterns were investigated using a CCD *** was found that the start-up process of these two SMpHps was rather *** the start-up p.r.od,no nucleation was observed,and the vap.r.plugs at the evap.r.tor U-bends were formed mainly due to the breakup of liquid *** the steady op.r.tion state,self-sustained oscillation with large amplitudes dominated the flow behavior when the inclination angle varied from 10° to 90°,but the nucleate boiling and bulk circulation were observed only in SMpHp #*** bubbly,slug/plug,annular/semi-annular,and wavy-annular flows were observed in both two SMpHps,the injection flow only appeared in SMpHp #2.

关键词： micro pulsating heat pipe flow visualization start-up flow pattern injection flow

ON THE AXIAL TrANSIENT rESpONSE ANALYSISOF THE SECTOr-SHApED HYDrODYNAMIC THrUSTBEArING-rOTOr SYSTEM IN A TUrBOEXpANDEr

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Chinese Journal of mechanical engineering 2000年第4期13卷 318-324页

作者： Zhu Qin Yi Xuemei (school of mechanical engineering，Shanghai University) 上海大学上海

A model for the non-linear axial vibrations of the hydrodynamic thrust bearing-rotor system in a turboexpander is described. The axial transient process of the system is investigated. The time-dependent form ofthe reynolds equation is solved by a finite difference method with successive overrelaxation scheme to obtain the hydrodynamic forces of the sector-shaped thrust bearing (SSTB). Using these forces, the equation of motion is solved by the fourth-order runge-Kutta method and the Adams method to predict the transient behaviour of the thrust bearing-rotor system (TBrS).Also,the linearized stiffness and damping coefficients of the oil film hydrodynamic SSTB are *** analyses of the axial transient response of the system under both linear and non-linear conditions are p.r.ormed. The non-linearity of oil film forces can significantly contribute to the axial transient response. Conclusions obtained can be applied for evaluation of the reliability of the TBrS.

关键词： Axial transient response Thrust bearing-rotor system Turboexpander

Microstructure and mechanical prop.r.ies of High-Cr Cast Iron Bars reinforced Hadfield Steel Matrix Composites

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Journal of Wuhan University of Technology(Materials Science) 2010年第3期25卷 464-468页

作者：牛立斌 Institute of Wear-resistance Materials School of Mechanical and Electrical EngineeringXi'an University of Architecture and Technology

To obtain the compatible material of high hardness and high toughness,Hadfield steel matrix composites,reinforced by high-Cr cast iron bars made of flux-cored welding wires,which were inserted into the Hadfield steel melt,were *** mechanical prop.r.ies of three materials,i e,composites for as-cast and quenching-water condition,as well as Hadfield steel,were *** results show that the alloy powder inside flux-cored welding wires can be melted by the heat capacity of Hadfield steel melt and solidify into high-Cr cast iron *** impact toughness of the composite for quenching-water condition is higher than that of the composite for as-cast condition and is lower than that of the Hadfield steel,but it can still meet the requirements of hardness and toughness in industrial *** of load variation,composite for quenching-water condition shows better wear resistance than those of the composite for as-cast condition and Hadfield *** modified fracture toughness and wear resistance of composites are attributed to not only the combining actions of Hadfield steel matrix and high-Cr cast iron bars,but also the effect of heat treatment.

关键词： composites flux-cored welding wires impact toughness hadfield steel

Novelty Detection Methods and Novel Fault Class Detection

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武汉理工大学学报 2006年第S2期28卷 767-771页

作者： ZHANG Jiafan HUANG Zhichu WANG Xiaoming (school of mechanical and electrical engineering,Wuhan University of Technology,Wuhan 430070,china, school of mechanical and electrical engineering Wuhan University of TechnologyWuhan 430070China

The ability to detect a new fault class can be a useful feature for an intelligent fault classification and diagnosis *** adopt two novelty detection methods,the supp.r. vector data description (SVDD) and the p.r.en density estimation, to represent known fault class samples,and to detect new fault class *** exp.r.ments on real multi-class bearing fault data show that the SVDD can give both high novelty detection rate and target recognition rate,respectively for the prescribed’ un- known’ fault samples and the known fault samples by choosing the ap.r.priate SVDD algorithm p.r.meters;but the p.r.en densi- ty estimation only give a better novelty detection rate in our exp.r.ments.

关键词： novelty detection supp.r. vector data description(SVDD) p.r.en density estimation fault diagnosis

Kinetics analysis of volume phase transition of intelligent neutral thermo-sensitive hydrogels

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Science china(physics,Mechanics & Astronomy) 2008年第5期51卷 532-540页

作者： WANG XiaoGui1 & LI YiQuan2 1 College of mechanical engineering,Zhejiang University of Technology,Hangzhou 310032,china 2 school of mechanical & Electronic engineering,Changchun University of Science and Technology,Changchun 130022,china 1. College of mechanical engineering Zhejiang University of Technology Hangzhou 310032 China 2. school of mechanical & Electronic engineering Changchun University of Science and Technology Changchun 130022 China

In this work,utilizing the first law of thermodynamics and the Flory mean-field theory,the kinetic deformation studies concerning the volume phase transition of the neutral thermo-sensitive hydrogels were p.r.ormed *** hydrogel was assumed as a biphasic mixture medium in the framework of the continuum mixture *** the energy conservation of the thermodynamics system of the hydrogel,the governing equations for the kinetics of the nonlinear large deforma-tion were *** explicit analytical expressions of the effective stress tensor and the chemical potential of the fluid of the thermo-sensitive hydrogel pNIpA were also obtained from the Helmholtz free energy,which can model the steady-static volume phase transition quantitatively.

关键词： thermo-sensitive hydrogel volume phase transition effective stress energy conservation

CALCULATION OF FUZZY rELIABILITY IN THE CASE OF rANDOM STrESS AND FUZZY FATIGUE STrENGTH

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Chinese Journal of mechanical engineering 2000年第3期13卷 197-200,223页

作者： Huang Hongzhong (school of mechanical engineering, Dalian University of Technology) 大连理工大学辽宁大连

The fuzzy sets theory is introduced into the fatigue reliability analysis. The concepts of maximizing set and minimizing set are developed to decide the ordering value of each fuzzy number, and these values can be used to determine the order of the fuzzy numbers. On the basis of the works mentioned above, the membership function defining the fuzzy safety event can be calculated, and then the fuzzy reliability in the case of stress and fuzzy fatigue strength is deduced. An example is given to illustrate the method.

关键词： Maximizing set Minimizing set Total utility value Fatigue strength Fuzzy reliability