Table of Content

29 January 2010, Volume 44 Issue 01 Previous Issue    Next Issue

Metallography and Metallurgical Technology

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APulsed YAG Laser Welding of in situ TiB2 Particulate Reinforced ZL101 Matrix Composite CUI Haichao,LU Fenggui,TANG Xinhua,YAO Shun,LOU Songnian 2010, 44 (01):  1-0005.  Abstract ( 4828 )   Save Pulsed laser welding of in situ TiB2 particulate reinforced ZL101 aluminum matrix composites was carried out. The effects of pulse frequency on the formation of bead and microstructure were studied. The results show that the formation of bead is good, and the porosity is decreased due to the effect of stirring of pulsed laser on the molten pool. The clusters of TiB2 get finer and distribute more homogeneously in the bead than that in the base metal. The stirring effect decreases when the pulse frequency is up to 200 Hz so that much porosity occurs and the clusters get larger. Moreover, the penetration depth is decreased with the pulse frequency increasing. The grain is very fine in the bead and TiB2 particles are located at the grain boundary. The values of hardness are uniform in the bead, higher than that in the base metal. There is no interface reaction to produce brittle products between the TiB2 and Al matrix so that it keeps the strengthening effects of reinforcement. Related Articles | Metrics

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ATopology Optimization of Blank Holder Structure of Stamping Die for Forming Complicated Automotive Part of HighStrength Sheet Metal TANG Yucheng;XU Dongkai;CHEN Jun 2010, 44 (01):  6-0010.  Abstract ( 3839 )   Save Based on die structure analysis, an SIMP based die structure topology optimization model was proposed. An optimal design method for binder part was established, aiming to reduce die weight. Optimization of binder structure of a floor member part of DP590 was studied. Compared with current design, optimally designed binder can reduce 50% weight. And the critical displacement and maximum stress are not affected. Related Articles | Metrics

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Martensitic Transformation in X12CrMoWVNbN10-1-1 Ferrite HeatResistant Steel HAN Lizhan,GU Jianfeng,PAN Jiansheng 2010, 44 (01):  11-0015.  Abstract ( 4068 )   Save Dilatometric studies on X12CrMoWVNbN1011 ferrite heatresistant steel were carried out to investigate the martensitic transformation under different austenization conditions. When the austenitizing temperature increases from 1 010 ℃ to 1 200 ℃ and the holding time keeps at 15 min, Ms and Mf increase with the increasing of austenitizing temperature. When the austenitizing temperature keeps at 1 070 ℃ and the holding time changes from 5 min to 20 h, Mf increases with the increasing of the holding time, and Ms increases with the increasing holding time only for the first 3 h, and then reaches a constant value of 460　℃　when the holding time exceeds 3 h. A new kinetic equation for martensitic transformation for this steel austenitized at 1 070 ℃ was obtained based on the dilatometric curves tested, which sets up the relationship between the volume fraction of martensite, transformation temperature and the austenization holding time. Related Articles | Metrics

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AMicroarc Oxidation Behaviors of AZ91D Magnesium Alloy in Different Electrolytes LIU Bin,ZHANG Puliang,WANG Jinqing,ZHANG Dong,ZHOU Jinfang,YANG Shengrong 2010, 44 (01):  16-0024.  Abstract ( 3676 )   Save Ceramic coatings were produced on AZ91D magnesium (Mg) alloy by microarc oxidation (MAO) technique in three different electrolytic solutions and at different oxidation times. The morphology, microstructure and composition of oxidation coatings were investigated by scanning electron microscopy (SEM) and Xray diffraction (XRD), respectively. Moreover, the bonding strength between ceramic coatings and AZ91D Mg alloy, as well as corrosion properties of coatings prepared in different electrolytic solutions and at different oxidation times were also evaluated with an MFT4000 tester and a potentiodynamic polarization tester. The experimental results show that the surface morphologies and the compositions of oxidation coatings are different in different electrolyte systems. The corrosion resistance of AZ91D Mg alloy treated with MAO technique increases obviously. Moreover, the bonding strength between ceramic coatings and AZ91D Mg alloy oxidated for 15 min is the biggest among the prepared samples. Related Articles | Metrics

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Simulation of Nonmassing Behavior of Polycrystalline Copper under Cyclic Strain Condition Yuanyuan,DONG Jiwei,FENG Miaolin 2010, 44 (01):  21-0024.  Abstract ( 3631 )   Save A cyclic plastic model in which an additional term is conducted into the evolution of backstress in order to predict nonmassing behavior of material was employed. Based on radialreturn method and back Euler integration, new stress and backstress contributions were obtained, tangent stiffness matrix for global iteration was deduced as well. The model was implemented into the commercial finite element software ABAQUS by usersubroutine UMAT. Examples were approached for polycrystalline copper which is typical nonmassing material. The results show that the finite element simulation agrees well with the experimental data. Related Articles | Metrics

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Thickness Effect on Grain Growth in Nanocrystalline Films AN Zhinan,DING Hong,RONG Yonghua 2010, 44 (01):  25-0030.  Abstract ( 3566 )   Save Various stagnation effects of grain growth in nanocrystalline materials have been found, but thickness effect is hardly investigated. This paper presented an anisotropic Monte Carlo (MC) algorism to stimulate grain growth in nanofilms with different thicknesses in annealing process. The simulation results reveal that thickness effect begins to be exhibited only when the average grain size reaches 0.8 to 1.2 times of the thickness of the films, not in the whole process of grain growth. Through introducing thickness factor, the paper modified Burke’s grain growth kinetic model and obtained a new equation in better accordance with the simulation results as well as the physical model of thickness effect. Related Articles | Metrics

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Ferrite Grain Refinement through Strain Induced Transformation in SPHC Steel WU Laizhi,CHEN Jun,ZHANG Hongbing,CUI Zhenshan 2010, 44 (01):  31-0035.  Abstract ( 3605 )   Save The single hot compression tests of SPHC steel were performed using a Gleeble1500 thermomechanical simulator. The characteristics of strain induced transformation and ferrite grain refinement were investigated through analyzing the stressstrain curves and metallographic structures. The results show that very fine ferrite grains of about 1.6~4.6 μm can be obtained by the deformation at 750~830 ℃, due to the occurrence of SIFT. Decreasing deformation temperature leads to increase the chemical driving force for austenitetoferrite transformation and thus leads to refine ferrite grain. The size and volume fraction of ferrite grains decrease with increasing strain rate at the same strain level. Related Articles | Metrics

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Martensitic Transformation in Au-Cu-Al Alloy System GU YiJia,JIN Mingjiang,JIN Xuejun 2010, 44 (01):  36-0040.  Abstract ( 3516 )   Save Three heat treatment processes were carried out to study the ordering of the parent phases in AuCuAl alloys. The influence of its A2B2L21 ordering transformation on martensitic transformation were analyzed, which contains the starting martensitic transformation temperatures(Ms), the structure of martensite and parent phases and the reason why no martensitic transformation was produced after 400 ℃ annealing followed by cooling with furnace. The results indicate that the sample that aged at 100 ℃ for more than 1h and then quenched into ice water (Heat treatment process II), can transform to martensite and show surface relief, as well as the sample directly quenched into liquid nitrogen from 650 ℃ (Heat treatment process I). Both of their structures are bodycentered tetragonal (bct). During the aging process, the parent phase gets more ordered, and consequently the Ms is greatly lifted. Therefore, the parent phase transforms to martensite more completely. In addition, as the sample aged at 400 ℃ for 2 h and then cooled with furnace (Heat treatment process III). A more ordered parent phase can be obtained, which probably transforms to a new phase with bct structure through the nucleation and growth mechanism. Related Articles | Metrics

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Speed Planning and Segment Connection in High Speed Machining YANG Lin,ZHANG Chengrui,WANG Ke,LI Peng 2010, 44 (01):  40-0041.  Abstract ( 3579 )   Save A speed planning method was presented in high speed machining of complex shape parts. After lookahead process, a time division based acceleration/deceleration interpolation algorithm is used to implement discrete speed control. Computational error caused by noncontinuity is eliminated by deceleration phase compensation and smooth connection processing between segments. The experiment shows that the proposed algorithm satisfies the requirements of interpolation accuracy and machining efficiency in high speed machining. Related Articles | Metrics

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OrthogonalTesting Experimental on MicroUltrasonicMachining of MicrocrystallineMicaCeramic WANG Dan,ZHAO Wansheng,KANG Xiaoming,GU Lin,WEI Hongyu 2010, 44 (01):  46-0050.  Abstract ( 3765 )   Save Microultrasonicmachining (microUSM) experiments were carried out on 530 μmthick microcrystallinemicaceramic（MCMC）slices with workpiece vibration and using silver tungsten alloy as tool materials. The experiments were designed by orthogonaltesting method considering five factors and two levels to investigate the influences of ultrasonic amplitude, tool feed rate, tool rotate speed, abrasive particle size and abrasive concentration on tool volume wear rate in the microUSM of MCMC. Based on the experiments, a 80 μm through hole was machined successfully on 530 μmthick MCMC slice with the optimized microUSM parameters, and the taper of the hole is less than 0.5°. Related Articles | Metrics

Communication and Transportation

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Bending Moments Study on the Cutterheads of Shield Machines Excavating in Composition Geologic Strata ZENG Xiaoxing,YU Haidong,ZHANG Kaizhi,WANG Hao 2010, 44 (01):  51-55.  Abstract ( 4165 )   Save The excavation surface model of the composition geologic strata for the shield machine was established, in which the soft soil and hard rocks are taken into account simultaneously. In terms of the cutting mechanism of the individual disc cutter and drag scraper, the total bending moment model on the cutterheads of shield machines was proposed. The bending moment behavior was discussed when the shield machine excavates in the composition geologic strata. The results show that the bending moments at x and y directions may be described by the cosine and sinusoid curves, respectively. The amplitude of the bending moment decreases with the increase of the fraction of soft soil on the excavation face. The average moment is maximal when the ratio of the soft soil and hard rock is about 50 percent. Related Articles | Metrics

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Hydrodynamic Characteristics of Tension Leg Platforms in Ocean Internal Solitary Waves YOU Yunxiang1,LI Wei1,SHI Zhongmin2,QU Yan2,XIAO Yue2 2010, 44 (01):  56-0061.  Abstract ( 4362 )   Save Based on the mKdV theory of internal solitary waves in a twolayer fluid, a theoretical model for analyzing the interaction of internal solitary waves with tension leg platforms was presented by using coupling motion equations of six degrees of freedom for the floating body combining with the modified Morison formula. The observational data near the Dongsha Island were used as the characteristic parameters of the internal solitary wave, the characteristics of hydrodynamic load and motion response, as well as tension changs of the tethers for the ISSCTLP due to such an internal solitary wave were computed and analyzed. The results show that internal solitary waves will give rise to sudden impact load and motion response with the large amplitude, as well as remarkable increase of the tether tension. Therefore, the influence of internal solitary waves on the hydrodynamic characteristics of the deepsea platforms including TLP can not be neglected in their designs and applications. Related Articles | Metrics

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Optimization Design of Vehicle Panel Selection Based on Sequential Response Surface Method ZHANG Yong1,LI Guangyao2 2010, 44 (01):  62-0067.  Abstract ( 4130 )   Save An optimal material selection method of vehicle was proposed by combining a sequential response surface method and the simulation annealing algorithm. The method was applied to the safety study of side impact, by which the materials of each part of the collision site were selected on the optimization design. The results show that a reasonable material match of side collision parts is achieved by optimizing design, and the safety of side impact of the vehicle has the notable improvement. Related Articles | Metrics

Architechural Science

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An Explicit Temporal Discretization Characteristic Based Split Algorithm and Its Application for Flow Past Bluff Body ZHAO Yaojun，ZHOU Dai,LI Lei 2010, 44 (01):  68-0073.  Abstract ( 4013 )   Save An Explicit Temporal Discretization Characteristic Based Split Algorithm and Its Application for Flow Past Bluff BodyZHAO Yaojun，ZHOU Dai,LI Lei(School of An explicit temporal discretization characteristic based split (CBS) algorithm was developed along the characteristic of the momentum equation with holomorphic differential form and by introduction of the coordinate transformation on the characteristic of the momentum. In the developed algorithm, the second order time precision is reached and the properties of the original CBS technique are remained. Furthermore, a series of the numerical simulation of unsteady flow with low Renolds number past a circular cylinder and a square cylinder was carried out by present algorithm and some comparisons between computational and experimental results of both drag and lift coefficients of bluff bodies were made. Finally, the flow fields around a single circular cylinder and two circular cylinders with sidebyside arangement were numerically investigated respectively. It is showed that the present algorithm is fit for the simulation of flow field with low Renolds number. Related Articles | Metrics

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tudy on Anticrack and Waterproof Technique of Polypropylene Fiber in Subway Station Concrete Structures sMA Hongwang1,WANG Yiqun2,XU Zhengliang3,LI Taiwen3,WU Yongxiang1,YAN Xiaodong4 2010, 44 (01):  74-0079.  Abstract ( 3771 )   Save The crack and leakage in concrete structure of subway stations is a difficult problem and need to urgently resolve in the near future. This paper presented adding polypropylene fiber to concrete, and the volume content of polypropylene fiber is determined by limit state design. This method was used in one subway station of Shanghai Rail Transit Line 7. The experimental results indicate that polypropylene fiber can improve the anticrack and water waterproof proof performance of concrete structures, satisfy the design requirements of subway station. Related Articles | Metrics

Petroleum,Natural Gas Industry

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Analysis on Combustion of Oil Sludge from Shengli Oil Field ZHOU Lingsheng,JIANG Xiumin,LIU Jianguo,WANG Hui 2010, 44 (01):  80-0084.  Abstract ( 3760 )   Save The oil sludge’s combustion and pyrolysis TG and DTG curves were obtained through thermogravimetric analysis experiments on the properties of oily sludge from ShengLi oil field. The differences of combustion and pyrolysis thermal curves were analyzed. The TGDTG method was employed to determine the ignition and burnout temperatures at different heating rates.The differences of the ignition and burnout temperature and combustion characteristic index at different heating rates demonstrate that the heating rate has some impacts on the oil sludge combustion. CoatsRedfern integral model was adopted to obtain the combustion kinetic parameters including activation energy, preexponential factor and reaction order. The results show that, with the increase of the heating rate, the oil sludge’s combustion rate, the ignition and burnout temperatures of oily sludge, and the calculated value of oil sludge’s combustion kinetic parameters such as activation energy would increase. Related Articles | Metrics

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Quantitative Analysis of Main Parameters on Cryogenic LNG Offloading from LNGFPSO GU Yan，JU Yonglin 2010, 44 (01):  85-0089.  Abstract ( 3406 )   Save Based on the conceptual design of LNG offloading system for LNGFPSO (liquefied natural gas floating production storage and offloading unit), a 1∶1 model of the floating LNG offloading process from LNGFPSO to LNG carrier was established. Detailed simulations were conducted and the main parameters, in particular the influences of the flow rate and the height difference of pipeline on the pump head and BOG (boil of gas) of the LNG offloading processes were quantitatively analyzed with the Aspen plus software. The results indicate that there are the dissimilar influences of the flow rate on the pump head and BOG therefore there would be an economic flow rate for practical design. The height difference of pipeline has obvious influence on the pump head for LNGFPSO offloading. Related Articles | Metrics

Atomic Energy Technology

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ThermalHydraulic and Neutronics Analysis for MultilayerFuel Assemblies of Mixed Spectrum Supercritical Watercooled Reactor LIU Xiaojing，YANG Ting，YAN Yong，CHENG Xu 2010, 44 (01):  90-0094.  Abstract ( 3471 )   Save thermal hydraulic and neutronphysical performance of the two multilayer fuel assemblies was investigated with a coupling approach. The results show that the hot channel factor and the maximum cladding temperature in the thermal fuel assembly can be kept significantly below the design limit using the multilayer concept. A sufficiently large negative temperature reactivity coefficient of coolant and the breeding feature can be achieved in the fast spectrum zone with the multilayer fuel assembly design. The results obtained so far show that the multilayer concept is feasible and promising. Related Articles | Metrics

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Analysis for Vibration and Noise Problem of Main Steam 　Isolation Valve with Pipelines XU Zheng，WANG Dezhong，ZHANG Jige，ZHOU Wenxia( 2010, 44 (01):  95-0100.  Abstract ( 3812 )   Save Numerical simulation with finite element method was used to analyze the unstationary characteristic of inner 3D onflow field for the main steam isolation valve (MSIV), the pipeline frame modal and the valve chamber acoustic modal. Based on the two methods of timeaverage flow analysis and large eddy simulation (LES), this paper tries to find the reason and principle of onflow eddy brought by the reduced aperture. The frequency range for the possible vibration and noise of valve pipeline was obtained, which was further proved by the experiment. The result indicates that, the main frequency of noise source engendered by the onflow eddy is close to the certain order connatural acoustic frequency of valve chamber, subsequently the acoustic chamber resonance acts as the main reason for the overhigh vibration and noise. From the onsite measurement which was acquired by laying acceleration transducers at different locations on the MSIV pipeline under real working condition, the multiplefrequency matches with the acoustic chamber resonance frequency. Related Articles | Metrics

General Industrial Technology

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Column Arrangement Optimization on Horizontal Tube Bundles of Falling Film Evaporators YANG Li1,WANG Wen1,BAI Yunfei2 2010, 44 (01):  101-0105.  Abstract ( 4171 )   Save An analysis about optimizing the column arrangement of horizontal tube bundles in falling film evaporators was carried out with numerical simulation by distributed parameters in large compression refrigeration systems. In this simulation, the model considered the evaporation heat transfer performance on horizontal copper tube bundles with liquid refrigerant HFC134a. The impacts of some factors, such as the column number of falling film tube bundle and the number of flooded tube row on the evaporator performance were analyzed. In addition, a parameter of uniformity factor of mass flow field was set up to evaluate the heat transfer performance of evaporators. The results indicate that the less the column number of the falling film tube bundle is arranged, the less the dry patches on falling film tube surfaces, the greater the uniformity factor of mass flow field and the better the heat transfer performance of evaporators under the same flooded tube rows. Related Articles | Metrics

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A Center Detection Algorithm of Nondiffracting Beam Based on Ring Filtering BI Xiaowei1,ZHU Limin1,ZHAO Bin2 2010, 44 (01):  106-0110.  Abstract ( 3493 )   Save Considering that nondiffracting beam is composed of a series of concentric circles, a center detection algorithm was proposed using all the information of the beam. This algorithm firstly calculates the average light intensity in a circle, secondly figures out the sum of the absolute value of light intensity difference Q(r) in this circle, then identifies the sum of Q(r) in all the circles as the objective function, so the center point is determined through the search of the minimum value of the objective function using NelderMead simplex method. Furthermore, this algorithm is optimized, using several circles instead of all circles to calculate the objective function. The experimental results show that the average time of this algorithm is less than 210 ms and the positioning accuracy can reach 0.1 pixel. Related Articles | Metrics

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A Flow Characteristics Model of Electronic Expansion Valve Considering Choking Characteristics CHEN Liang,CHEN Jiangping,LIU Jinghui,CHEN Zhijiu 2010, 44 (01):  111-0115.  Abstract ( 3874 )   Save The choked refrigerant flow characteristics of electronic expansion valve (EEV) was analyzed. A metastability coefficient was proposed by employing the homogeneous equilibrium flow model and frozen flow model to depict the flow characteristics of EEVs, and the coefficient was applied to build a mass flow model of EEV. The modeling results were compared with the experimental data and the deviation of the predicted metastability coefficient by the model is in the range of -8.59% to 7.56%. Related Articles | Metrics

Radiao Electronics, Telecommunication Technology

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Effect of Bonding Parameters and Chip/Substrate Thickness on Warpage of ChiponGlass Packaged with Nonconductive Film ZHANG Jianhuaa,b,YUAN Fangb,ZHANG Jinsongb 2010, 44 (01):  116-0119.  Abstract ( 4517 )   Save Chiponglass (COG) is one of the promising technologies in liquidcrystaldisplay packaging. This paper executed a thermalstructure coupling field to simulate the warpage in thermocompression bonding with nonconductive film(NCF). The results reveal that the temperature of bonding head is the most important factor on COG warpage, the bonding force and temperature of substrate decline to influence COG warpage in sequence. Although increasing the thickness of substrate can decrease warpage, the change of IC thickness has not a strong relationship to warpage. This is expressed that the thicker substrate enhances the resistance of deformation for the whole COG module, which suppresses warpage effectively.4 Related Articles | Metrics

Engineering Mechanics

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Flow Boiling on a Microscale Surface under Pulse Heating CHEN Gang,QUAN Xiaojun,CHENG Ping 2010, 44 (01):  120-0123.  Abstract ( 3589 )   Save Using MEMS technology, a Pt microheater (60 μm×100 μm) fabricated on a glass wafer was placed in a siliconbased microchannel of trapezoidal cross section. With the aid of a highspeed CCD, flow boiling phenomena on the surface of the microheater in the microchannel under pulse heating were observed and recorded. At a given mass flux, nucleate boiling and film boiling began to appear on the microheater with increasing heat flux. A flow boiling map, showing the effects of heat and mass flux on the nucleate and film boiling regimes on the microheater at a pulse heating width of 2 ms, was presented. It is found that the nucleate boiling was changed to film boiling as the heat flux supplied by the microheater is increased. Furthermore, increasing mass flux increases the heat flux required for the incipience of nucleate boiling and film boiling on the microheater in the microchannel. Related Articles | Metrics

Weapon Industry

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Empirical Formulas Prediction and CFD Calculations of Torpedo’s Propulsion Characteristics YANG Qiongfang，WANG Yongsheng，LIU Kai 2010, 44 (01):  124-0129.  Abstract ( 4520 )   Save Empirical Formulas Prediction and CFD Calculations of Torpedo’s Propulsion Both empirical formulas and CFD calculation were used to predict torpedo’s propulsion characteristics and the hydrodynamics of the bare hull and the ducted propulsor. The result shows that within the speed from 10.29 to 25.72 m/s the difference between numerical calculated drag coefficient of the ball hull and the sum value, which is friction resistance coefficient of a flatplate and the rest drag coefficient, is less than 5.2%, which shapes the precision and reliability of the drag formula suitable for the profile of the hull. The CFD calculated open water characteristics of the ducted propulsor show good agreement with the experimental data in the range of J=1.6-2.0, with the difference less than 5%. And both the calculated thrust and torque of the propulsor and the system propulsion efficiency differ by less than 5% from the values obtained by the empirical formulas that fit to predict the torpedo propulsion performances propelled by the counterpropeller, which presents the usability of the empirical formulas to the ducted propulsor. Related Articles | Metrics

Engineering Mechanics

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Simulation of Delamination Buckling by Fiber Bridges ZHANG Zhenxing，XIAO Gang，LI Siping 2010, 44 (01):  130-0133.  Abstract ( 3991 )   Save Structure buckling analysis was investigated using ANSYS finite element theory. The numerical analysis of the delamination buckling was made to the thin rectangular plate which is affected by fiber bridges, basing on the finite element theory. The result shows that the critical load of the delamination buckling is greatly enhanced taking the fiber bridges into consideration. The mode of buckling is grown in the postbuckling of the delamination and the multiple modes are excitated. The partialbuckling phenomena also happen after the buckling. The greater the constrain stiffness, the smaller the buckling region. And the range of the patialbuckling is more closer to the end in which the load is applied. The characteristic length of the delamination buckling, that which is the length of half wave, decreases and the critial load increases as the increasing of the stiffness. Related Articles | Metrics

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A Free SurfaceTraced Method for Moving Particle Semiimplicit Method PAN Xujiea,ZHANG Huaixina,b,SUN Xueyaoa 2010, 44 (01):  134-0138.  Abstract ( 4193 )   Save A free surface traced method was put forward for moving particle semiimplicit (MPS) method. In simulation of MPS, the free surface is traced by the number density parameter between the explicit step and implicit step, and the number density parameter is changed because of the first explicit step, some nonfree surface particles are treated as free surface due to the small number density parameter which is caused by explicit step. The new free surface traced method is detected by neighbors, the zone of a particle is divided into eight parts, and the particle is treated as free surface when no neighbor particle in any two neighboring parts. Taking into account that the number density parameter has a higher efficiency for free surface, the neighbor detected method is mixed with the number density parameter, and the neighbor detected method is only used in the range of number density when mistreatments are most likely to happen. The result shows that the neighbor detected method is efficient for free surface, and mixed use only has a little effect on the efficient of the simulation. Related Articles | Metrics

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Influence of Thickness on the Wavelet Package Relative Energy Feature of Coated Materials with Interface Flaws XU Bing，XU Jinquan 2010, 44 (01):  139-0143.  Abstract ( 3335 )   Save Based on the wavelet package relative energy feature, the sensitivity of this feature to the interface flaws with different coat thickness was analyzed through the numerical simulation by finite element method. The results show that this wavelet package relative energy feature from the acceleration signals can reflect the interface crack location and size and the sensitivity is more obvious when the coat is thinner. Related Articles | Metrics

Mathematics

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Remapping Algorithm of Physical Variables Used in Arbitrary LagrangianEulerian Simulation ZHUANG Xincun,WU Yu,ZHAO Zhen,XIANG Hua 2010, 44 (01):  144-0148.  Abstract ( 3880 )   Save During the arbitrary LagrangianEulerian (ALE) simulation, once the mesh moving, the variables related to the deformation history must be transferred from the old mesh to the new mesh so as to continue the next computational step. According to the theory of water wave transportation in hydrodynamics, the remapping procedure can be assumed as an advection problem. In this study, a remapping algorithm based on the combination of explicit second order RungeKutta discontinuous Galerkin method and limiter was used, which can eliminate the dispersion and local oscillation of the remapping result, and further improve the calculation accuracy of ALE simulation. Related Articles | Metrics