bluuebunny/crossref_metadata_2025 huggingface dataset:
Fabrication of Ni-Base ODS Alloys via Reactive Ball Milling
Authors: Liu Ye , Qu Xuan Hui , Zhang Lin , Qin Ming Li , Zhang De Zhi , Jia Bao Rui , Kang Qi Ping , Khan Dil Faraz
Published: March 2013

By the use of YH2 and NiO, oxide particles were introduced in Ni-base ODS alloys through reactive ball milling, which shows the advantages of energy-saving and uniform distribution of the oxide dispersion. The mophological and size evolution of ball milled powder were investigated, and the synthesized oxides were characterized. The results shows that the ball milled powder exhibits the feather of severe deformation. The disintegration of particles occurs after 10 h, and the balance of powder welding and fracturing is achieved around 25 h. the formation of Y2O3 with the size of 20~50 nm was confirmed by XRD and TEM results.
The Influence of Inorganic Carbon on Anaerobic Ammonia Oxidation
Authors: Fu Jin Xiang , Jiang Xi , Zhao Jun
Published: March 2013

Through running anaerobic ammonia oxidation reactors for a few days, we found that inorganic carbon source has great influence on anaerobic ammonia oxidation reactions. The inorganic carbon source increasing, the effect of anaerobic ammonia oxidation bacteria reaction is much better and the processing rate is high. And if there are no inorganic carbon source, anaerobic ammonia oxidation reactions are running anomaly. The processing rate of nitrate nitrogen is about 80%, and the processing rate of ammonia nitrogen is only 30% or so. The anaerobic ammonia oxidation bacteria metabolic is getting worse and worse.
Parametric Study of Swage Ball for Hard Disk Drive Swaging Process Using Finite Element Method
Authors: Dheeravongkit Arbtip , Tirasuntarakul Narongsak
Published: March 2013

Ball swaging is a general method in head stack assembly process to permanently attach Head Gimbal Assemblies (HGA) on the actuator arm. In this process, the swage ball is guided by a pin through the inner base plate’s hole in order to deform the base plate to tightly attach to the actuator arm. However, the loosing problem can still be found quite often in the current swaging process. This research focuses on ball sizes and the number of balls used which currently no theoretical guidance in choosing the both parameters. Besides, the best combination of the both parameters can give the best swaging performance. The three-dimensional finite element model is created and analyzed to estimate the swaging performance according to the variation of both parameters by using the tightening torque and the fixing distance of base plate to determine the quality of the ball swaging process. The results from finite element method are treated as the sampling points which are used to create the interpolation in order to increase the considered cases to cover all happening cases from both parameters. After that, a searching algorithm is implemented to determine the most suitable ball size and the number of ball used for the process. By using the finite element analysis together with the interpolation and a searching algorithm, the optimal design parameters for a complex problem with multiple conditions of consideration can be easily found.
Thermodynamic Analysis of the Shock Compaction of W/Cu Granular Mixture Based on the Mesoscale Simulation
Authors: Zhang Xian Feng , Qiao Liang , Shi An Shun , Zhang Jiang , Zhang Yan Guo
Published: March 2013

Shock compaction is an important industrial manufacturing technology for metal powder mixture. In order to analyze the thermodynamic response of W/Cu powder mixture during the shock compaction process, numerical simulation is conducted based on the mesoscale model. The model is generated randomly according to the real morphology distribution statistics regularity. Shock wave is achieved by introduce a rigid wall moving towards the model. Therefore, effects of deformation morphology, temperature distribution and pressure distribution under different shock velocities are presented and discussed. This work could provide a detail understanding of thermodynamic response during shock compaction process in granular-level.
Experimental Investigation on Hybrid Technology of Ultrasonic Vibration Assisted Chemo-Mechanical Grinding (CMG) Silicon Wafer
Authors: Yang Wei Ping , Wu Yong Bo , Liu Jun
Published: March 2013

For the final finishing of the substrate surface, Chemo-mechanical polishing (CMP) is often utilized. Those processes are able to offer a great sur-face roughness, but sacrifice profile accuracy. On the other hand, Chemo-mechanical grinding (CMG) is potentially emerging defect-free machining process which combines the advantages of CMP. In order to simultaneously achieve high surface quality and high profile accuracy, CMG process has been applied into machining of large size quartz glass substrates for photomask use. In this paper, based on the characteristics of higher machining efficiency and higher surface quality of ultrasonic vibration machining, a new ultrasonic vibration assisted CMG of silicon wafer hybrid technique is achieved by designing elliptical vibrator with longitudinal mode and bending mode. The experimental results show that under the elliptic ultrasonic vibration assistance, the surface roughness is decreased significantly, the surface quality is improved obviously, and moreover caused little or even doesn’t lead to the surface damage.
Study on the Influence of Ultrasound Impacting to the Properties of 16 Mn Welded Joints
Authors: Sheng Yong Hua
Published: March 2013

In this article, the technology of ultrasound impacting is mentioned. The toe of 16Mn welded joints are treated by the ultrasound impacting, and the fatigue, hardness and residual compressive stress of the 16Mn welded joints are compared after treated by ultrasound impacting. The results shows that, the ultrasound impacting bring high residual compressive stress on the surface of the 16Mn welded joints, besides, the treatment of ultrasound impacting can improve the fatigue and hardness of the 16Mn welded joints, and when the impacting electric current is 1.5A, and the impacting time is 10 min, the fatigue and hardness of the sample is the best.
Copper Absorption by Glass Derived Hydroxyapatite Scaffolds Prepared by Dipping with Polymer Foam
Authors: Gu Dong Lin , Ou Hai Peng , Wang Jiao Jiao , Rüssel Christian , Liang Wen
Published: March 2013

Sodium calcium borate glass derived hydroxyapatite (G-HAP) scaffolds were prepared by dipping with polymer foam. The effects of glasses and ethyl-cellulose (EC) content on the porosity and compressive strength of the scaffolds were studied. The effects of different initial pH value and ions concentration on adsorption performance of copper ions in aqueous solutions were also investigated. The results showed that G-HAP scaffolds could immobilize copper ions in solution effectively. The mechanism of G-HAP scaffolds in immobilizing Cu2+ ions from aqueous solutions was investigated by the X-ray diffraction, Infrared Spectra and Scanning electron microscopy-Energy Dispersive Spectrometer.
Calculation Model Study on Damaging Stress of Hydraulically Created Fracture Propagation
Authors: Zhao Wan Chun , Wang Chen , Wang Ting Ting , Guan Bing
Published: March 2013

In order to describe hydraulically created fracture propagation’s characteristics of rock matrix exactly, in this paper, establishing a stress field ‘s calculation model of fracturing propagation tip , obtaining numerical method of fracturing propagation’s characteristics based on damaging and describing fracturing propagation’s characteristics combined with method of finite element. Research shows that the corrigendum between stress field ‘s calculation model of fracturing propagation tip and practical engineering are 0.64 percent and 1.43 percent respectively. Compared with the traditional method, the result is more exactly.
Oxygen Permeability of Ba0.5Sr0.5Co0.8Fe0.2O5+δMembrane after Surface Modification
Authors: Shen Zi Gang , Li Dong
Published: March 2013

The oxygen permeation fluxes of Ba0.5Sr0.5Co0.8Fe0.2O5+(BSCF) membranes coated by RBaCo2O5+ (R= Pr, Nd, Sm, Gd) thin layer were investigated. The oxygen permeation fluxes of BSCF membranes with RBaCo2O5+ (R112)R112 coating layer can be enhanced remarkably. And it is found that the reaction of R112 with BSCF also have effect on the oxygen permeation fluxes. Impurity formed by the reaction of Pr112 with BSCF block oxygen permeation. While NdBaCo2O5+ and SmBaCo2O5+, especially GdBaCo2O5+ have no serious reaction with BSCF, they are desirable materials for coating layer of oxygen permeation membranes.
Synthesis and Spectroscopic Properties of Novel Chiral Amino Acid Tailed Porphyrins
Authors: Xue Jun , Wang Ya Jun , Rao Ming Yi , Luo Guo Tian
Published: March 2013

A new L-amino acid tailed porphyrins and its Zinc(Ⅱ) complex were synthesized by L-amino acid and 5-(2-ethoylphenyl)-10, 15,20-triphenylporphyrin.FAB-MS, UV-vis, IR element analysis and chemical analysis were used to determine the structures of the porphyrin and zinc(Ⅱ) complex.
Optimal Design of Highway Piezoelectric Generators
Authors: Zhao Yan , Wang Song Wei , Li Yu Feng , Zheng Yin Huan
Published: March 2013

In this paper, the analysis of the loading condition and the piezoelectric coupler provides the theoretical basis for the design of the structure of highway piezoelectric generators. Based on the PZT-4, the paper constructs a mechanical model of piezoelectric ceramic stacks. The optimal size of a single chip and the encapsulating form of piezoelectric ceramic stacks are presented with the use of theoretical calculations and ANSYS simulations. The structure of the piezoelectric ceramic stacks is developed to optimize the structure of highway piezoelectric generators and ensure its structure stable and solid.
Dynamic Modeling and Simulation of the Basic Shaft Bearingless Motors
Authors: Chen Qiu Yue , Zeng Li
Published: March 2013

A dynamic coupling model of the bearingless motor is established. This test does some simulations of motor displacement, no load speed and tracking accuracy under certain performance indicators. Analysis and simulation results show that the system has a control strategy of high precision as well as good dynamic and static performance.
Prediction Model of Centrifugal Fan Performance Based on BP Neural Network
Authors: Zhang Lei , Hu Chen Xing , Zhang Qian
Published: March 2013

In view of the G4-73 type backward centrifugal fan widely used in power plant, training samples for orthogonal test is conducted. A Centrifugal fan performance parameters prediction model based on BP neural network is built. Through the contraction between the predictive value and samples, the accuracy of prediction model is verified. The maximum relative errors of total pressure and efficiency are respectively 0.974% and 0.3327% with the trained neural network to predict on each single test sample, which reaches the predetermined training accuracy, and can be used for fan performance prediction.
Research of Provincial Forest Fire Emergency Resource Management Platform
Authors: Zhou Cui
Published: March 2013

In order to strengthen informatization for forest fire emergency resources management, a framework of resource integration and information sharing was put forward. The construction goal, software and hardware structure and its function, emergency platform cantacting with other government and information update process were researched. Forest fire emergency resources in departments of interconnection and interflow, information sharing and emergency linkage were achieved.
Laser Profile Scanner Application for Micro Part Detection
Authors: Kuhfuss Bernd , Schenck Christian , Wilhelmi Philipp
Published: March 2013

Due to size effects production processes for macro parts are often not applicable to micro production. Especially the handling is more complicated. The approach to overcome these problems is to resize the parts to the macro world by producing them in linked parts. These structures use the base material as a substrate which keeps the micro parts interconnected. The small tolerances for micro parts demand a high precision positioning for the subsequent processing. An equidistant arrangement cannot be assured by the manufacturing processes. The micro parts must be identified within the linked parts by characteristic geometrical features and referenced separately with respect to the feed system. For this task the application of a laser profile scanner is investigated. For the data evaluation and the recognition of typical geometrical features a real-time capable algorithm with sufficient robustness against noise and measuring errors is developed. To validate the function of the algorithm test measurements are performed and compared to reference measurements done by microscopy.
Verification Mechanism for Online Responses in Criteria Prioritization
Authors: Lim Chia Yean , Khoo Vincent K.T. , Belaton Bahari
Published: March 2013

In online criteria prioritization questionnaires, the respondents are not given an opportunity to verify and deliberate the reasons for each response. This paper describes a novel way to acquire the reasons and contexts behind the prioritization of criteria or alternatives, through a verification mechanism together with a set of logical rules. Essentially, a respondent is expected to visually verify the online responses against the reasons behind the prioritization of each pair of alternatives or criteria. A rule-based approach is then adopted to validate and display the inconsistent responses. Each respondent is expected to correct all detected inconsistency by recording the appropriate reasons and contexts in some concept maps. The resulting verification mechanism could be further enhanced and used as an intelligent organizational knowledge creation and maintenance framework for personalizing a group decision support setting.
Research on Intelligent Flowmeter Calibration Software System Design
Authors: Chen Jiu Jun , Sha Yong Zheng , Cheng Ting , Xiao Gang , Mao Jia Fa
Published: March 2013

The calibration system is commonly used to test the meter accuracy. An intelligent and adaptive calibration software system is proposed as an upper computer application, which gathers, deals, and stores the signal data from the sensors, and analyzes the calibration result. Three main modules, i.e., PLC communication module, calibration module, and report module, are defined. The MEWTOCOL-COM communication proxy of Panasonic PLC is designed by using .NET SerialPort framework, and is used to transmit data between PC and hypogynous machine through serial communication. Based on the data processing, an enhanced static weighing method is used as a calibration algorithm to verify the flowmeter parameters, i.e., error rate, repeatability and so on. And the final report is generated by the adaptive report module. The results of experimental tests and actual running show that the system is highly efficient with low test cost and reliable performance.
A Hybrid Optimization Based on GPU Parallel Computing Method and its Application of Three Dimensional Large Eddy Simulations
Authors: Zhang Yu Xuan , Wu Song Ping
Published: March 2013

Using compute Unified device architecture (CUDA), a traditional computational fluid dynamics (CFD) program is paralleled and optimized based on graphic processing unit (GPU). The calculation process is divided into two parts as serial and parallel. Their main characteristics are analyzed and different optimization schemes are given. CPU (central processing unit) and GPU work respectively as flow control and high-speed parallel computation. Bandwidth between devices is applied effectively. Data transfer between devices is moderately improved to simplify algorithm. Finally, the method is verified by simulating a three-dimensional isotropic homogeneous turbulence flow field. The calculation uses large eddy simulation (LES) method with secondary filter and solves the three-dimensional N-S equations. The maximum grid number achieves 8,000,000 and takes 33 seconds each step. All calculations are using ordinary single desktop computer, optimized acceleration ratio can reach 9.
Discussion of the Construction Design Methodology Considering both Evolutionary Structural Optimization and 3D Printing Technology
Authors: Zhou Y.Y. , Chen Lian Meng , Zhao Feng Hua
Published: March 2013

Construction design, one of the oldest specialties in civil engineering, is a combination work of architectural design and structural analysis. By the development of computer technology, the idea of construction design has been revolutionary changed. This paper introduces a new construction design methodology considering both evolutionary structural optimization and 3D model printing technology. Instead of manual drawing and planning, computer-aided design (CAD) is the used to assist in the creation, modification, or analysis of an architectural design. Computer-aided design involves more than just drawing. In structural engineering area, by using the finite element analysis software (ABAQUS), evolutionary structural optimization (ESO) method can improve the design in defining shape, choosing material and calculating the tolerance of a construction. Finally, the computer designed digital model is made into a three dimensional solid object from the 3D model printer. The solid model can give a visualized view of the whole construction.
Robust Quantized Guaranteed Cost Control
Authors: Liu Wen Wei
Published: March 2013

In this paper, the robust state feedback guaranteed cost control problem for discrete-time systems with signal quantization is studied. A dynamic quantization control strategy is proposed with updating the quantizer’s parameter such that the system is asymptotically stable and the performance index is with a upper bound.
Adaptive Consensus of High Order Multi-Agent Systems with Unknown Nonlinear Dynamics
Authors: Zhang Yi , Yu Hui , Liu Gao Yang
Published: March 2013

In this paper, high order consensus problem of multi-agent systems with non-identical unknown nonlinear dynamics following an unknown and nonlinear leader is investigated in networks with fixed and switching topologies. By parameterizations of unknown nonlinear dynamics of agents in the system, neighbor-based adaptive consensus algorithms are proposed by incorporating consensus errors in addition to relative position feedback. Base on algebraic graph theory, Lyapunov theory, Riccati inequalities and PE condition, analysis of stability and parameter convergence of the proposed algorithm are conducted. Finally, a simulation in switching networks is worked out to illustrate the effectiveness of the theoretical results.
The Urban Sprawl and Urban Planning in Haikou
Authors: Liang Zhen Zhuang , Huang Wu
Published: March 2013

Rapid urban development and dramatic change of landscape have been recently witnessed in the developing city Haikou in China as a result of rapid economic development. In this paper, Dinamica which was a spatially explicit simulation model of landscape dynamics were used to simulate the evolution of Haikou during the period of 1989 to 2012.They are expanding from exist city cell, around the city center, along the transportation line, and rural resident spot. According to the spatial occupation reality of Haikouin 1996 and 2008, the simulation accuracy is greater than 82% . Dinamica model is considere d a useful tool for urbanization research. And we found that residential land development tools such as the Public Residential City Development (PRCD) and the Housing Construction Facilitating Support (HCFS) in Haikou are working to prevent sprawl or facilitate it.
Study on Water Resource Protection and Pollution Prevention of Mining Area
Authors: Yang Sai Ming
Published: March 2013

Freshwater resource in many parts of our country and the world is in shortage. Research on sustainable use of water resource is an advancing front topic.Based on analyzing the status of destroy and pollution of water resource in Nantun coal mining area, Countermeasures of water resource protection and pollution prevention in Nantun coal mining area are put forward.
Impact of Residential Real Estate Development on Green Construction
Authors: Guo Hong , Su Min Fang
Published: March 2013

It discussed green construction practice in residential real estate development projects in China, analyzed problems met on the implementation of green construction in residential real estate development, on this basis several suggestions on how to promote green construction in residential real estate development were proposed. Policy support and government supervision play the role of lead, promotion and enforcement in the process of green construction in residential real estate development. Green construction plays an important role in promoting sustainable development of residential real estate development and construction industry.
The Planning and Design of the Modern Residential Area from Green Building Perspective: Taking Chengxi Project of Taiyuan as an Example
Authors: Chen Yi Ru , Meng Cong Ling
Published: March 2013

The thesis analyses the early stage of the planning and design in Taiyuan xicun renovation project from the green building perspective. It summarizes the strengths and shortages on the basis of Four Conservations and One Protection (area conservation, energy conservation, water conservation, material conservation and environmental protection). By analyzing the problems in planning and designing modern residential area, this thesis aims to provide some suggestions to the green building idea.
Comprehensive Treatment for Shallow-Buried Mined-Out Area in Coal-Mining Region of Western China
Authors: Chen Qiu Ji
Published: March 2013

There were lot of shallow-buried mined-out area in the western China, which had severely affected the safety in production and the eco-environment. The viable treatment method was analyzed according to the characteristics of mined-out area. By companion, the comprehensive treatment method of excavation- backfill-eco-restoration was put forward. Then the key techniques for this method were analyzed. The strongpoint for this method was that the coal mine resource can be utmost utilize, the eco-environment problem can be thoroughly treated, and at the same time, it can solve the problem of lack of finances, and mobilize the initiative of the enterprises to participate in mined-out area treatment. It is suitable for shallow buried mined-out area with yard to store the excavation material. But the effect of treatment still needs a further monitor over a long period of time.
Study on the Criterion of Discriminant on Highway Collapse Disaster in Mountain Area
Authors: Yan Jian Long , Xu Zhang Jian , Zhang Yong , Shen Hong Jun
Published: March 2013

With the development of road construction in mountain area of China, the collapse disaster is increased because the high fill and deep cut of the road is more and more. And the great economic losses and casualties are caused by this kind of geological hazard. On basis of the development collapse summarizes the basic rules and types; this paper puts eight fast criterion of discriminant on highway collapse disaster in mountain area according to the character statistics analysis on engineering practice experience and collapse case. According to the development process of the stage on mountain highway collapse disaster, which includes early inoculation stage, middle potential stage and advanced induced stage. On the basis of the rapidly criterion of discriminant on highway collapse disaster in mountain area, this paper refines the five aspects in landform and physiognomy and geological structures, proposes the development process in criterion of discriminant on highway collapse disaster in mountain area. It’s hopeful that the research results can be provided the scientific guidance for the temporal discriminant of highway collapse disaster in mountain area.
Comparison of Two Hyperelastic Models for Carbon Black Filled Rubber
Authors: Li Ming , Hu Xiao Ling , Luo Wen Bo , Huang You Jian , Bu Ji Ling
Published: March 2013

Mooney-Rivlin model and Ogden model are frequently used by engineers for finite element analysis of rubber material. Before simulation, simple, biaxial and planar extension tests are always done to get the model parameters. In this paper, we compare these two hyperelastic models with experimental data produced under simple, biaxial extension and planar extension loading conditions. The ability of the two models to reproduce different deformation modes is analyzed. Both material parameters and the stretch range of validity of each model are determined.
Seismic Damage Investigation on Buildings of Qingchuan County in Wenchuan Earthquake
Authors: Li Wei , Li Shan You , Zhao Zhen
Published: March 2013

The seismic damage investigation data of 257 buildings in Qingchuan County during Wenchuan earthquake are statistically analyzed. The results indicate that the seismic damages of buildings with seismic design are obviously lower than those of buildings without seismic design, and the damages of the brick-wood structures are most severe, that of the bottom frame structures and masonry structures are second while that of the reinforced concrete frame structures are relatively slight.
Analysis of the Surface Soil EC Dynamics and the Economic Benefit under the Subsurface Drainage System
Authors: Yan Yu Min , Wang Xue , Hou Mao Mao
Published: March 2013

Subsurface drainage was known as an effective method to solve salinity problems, in this paper, two different subsurface drainage systems were designed to study how the system affect the surface soil EC(electric conductivity), besides, the economic benefits of the system were evaluated. Results showed that: under the drainage system, the surface soil EC was in a trend of fluctuant reduction, the desalination ratio of T1.1, T1.2, T2.1, T2.2 and CK was 13.5%, 11.2%, 14.8%, 12.6%, and 6.0% respectively; the surface soil EC would present an rising trend in an irrigation cycle on account of the evaporation and the groundwater level, compared with CK, the drainage treatments could better suppress the soil resalination; the calculation results of economic indexes proved that both T1 and T2 could gain favorable economic benefits, and T2 was preferable with higher EIRR (16.4%), ENPV (4536$/hm2) and EBCR (1.48). The results also suggest that the subsurface drainage system was practicable from ecological and economic angle.
The Numerical Study on Errors of Stress in Anisotropic Linear Elastic Material when Simplified as Orthogonal one
Authors: Li Lin , Yang Jin , Qian Xiu Qing , Zhang Hai Xia , Liu Zhi Cheng
Published: March 2013

Keywords: strain, stress, material constants, constitutive equation, anisotropy. Abstract. If the material is anisotropic, there are differences in stress distribution under the same boundary conditions when it was simplified as an orthotropic material. We established a simple finite element model for rectangular perforated planar material, in which one side was fixed, the opposite side was loaded with uniform force, and the other sides were set free. Based on this model we studied the difference of distribution of stress between anisotropic material and its simplified form, orthotropic material. The results showed differences in some cases quite large, the maximum relative error of extreme stress can reach 341%. In conclusions, this study does not support that the complex anisotropic materials are simplified to orthotropic materials. If researchers only concern the location of extreme stress, this study does not deny that the complex anisotropic materials can be simplified to orthotropic one.
Density Calculation of Saturated Cohesive Soil under Different States in Ningbo Area
Authors: Yuan Xiang , Gong Quan Mei , Zhou Shun Hua
Published: March 2013

Based on the elastic deformation theory, the formula to compute density of saturated cohesive soil in different states is derived by comparison of the strain stress relations in different states and conversions between soil parameters in three states. The density of saturated cohesive soil in Ningbo area under different states is measured by centrifugal model test. The feasibility of the computational method is verified compared with model test results. In practice, the corresponding density can be determined according to the moisture content variation of saturated cohesive soil so that waste of soil samples is avoided.
Strength Criteria of Jointed Rock Mass in Unloading Area
Authors: Wang Fei , Liang Xu Li , Du Jian Po
Published: March 2013

The strength properties of the rock under unloading conditions are essentially different from the rock under loading conditions. At present, the study on the mechanical properties of unloading rock mass is common, but the research for unloading strength properties of jointed rock mass, especially the influence of structural plane on unloading strength is seldom. The paper studied the failure characters of unloading rock mass, and the influences of structural plane properties on unloading strength based on triaxial test are considered emphatically. Finally the strength criterion of unloading rock mass is proposed in this paper.
The Stress Formula of Soil under Vertical Line Load
Authors: He Wan Cheng , Li Guang Fan , Wu Xiao Feng , Wang Xiao Liang
Published: March 2013

Using integral method, the stress formula of soil for arbitrary Poisson's ratio under vertical line load was detailedly and completely derived based on Melan integral. The result shows that when the line load acting on the ground surface for arbitrary Poisson's ratio of soil, the stress formula is equivalent to the formula for Poisson's ratio of 0.5. Owing to such stress bubble graphics haven't appeared in Chinese soil mechanics textbooks, we give a detailed mapping of stress bulbs under vertical liner load.
Site Investigation of a Loess Slope for a Field Irrigation Test
Authors: Zhou Y. F. , Tham L. G. , Xu L. , Dai F. C.
Published: March 2013

The Heifangtai plateau, having an area of about 14 km2, has experienced more than 70 loess landslides since 1960s. Aiming at investigating the slope instability induced by irrigation, a field test was proposed. As an important part of the field test, a detailed site investigation was conducted systematically. The topographical details of a typical loess slope at Heifangtai were obtained by a 3D laser scanner. The cracks and the plan view of the site were obtained using GPS. The lithological profile, groundwater level, sampling and soil permeability, were also investigated respectively. On the basis of the site investigation, the field test was conducted successfully.
Numerical Simulation of Land Subsidence in Hangu-Tianjin
Authors: Qin Long , Xu Pei Hua , Yang Zhi Shuang
Published: March 2013

The Hangu research area is belonged to the typical inshore soft soil area. The engineering geological properties of soil in the research area is rather poor. With the rapid development of Tianjin and the improvement of people’s living standards, with the increasing demand of people’s lives of with water and industrial water, a lot of groundwater exploited caused groundwater elevation changes and resulted in pore water pressure changes and leaded to effective stress changes of soil, which eventually caused land subsidence . Numerical analysis method is used to this paper to research land subsidence of Hangu,Tianjin.
Experimental Research on Compression Characteristics of Compacted Loess
Authors: Wang Min , Bai Xiao Hong
Published: March 2013

A series of compression tests were conducted on the samples taken from compacted soil site in Lulling, in order to investigate the compressibility of compacted loess in different water content and different compaction energy. Through statistics analysis of the testing data, the stress-strain curve of compacted loess could be expressed with Hyperbolic form. And the relation between initial tangent modulus and water content change coefficient was founded by introducing the water content change coefficient. The result shows that at the same compaction energy, the initial tangent modulus decreases and the ultimate strain increases as water content increases; while at the same water content change coefficient, the initial tangent modulus increases and the ultimate strain decreases as compaction effort increases.
Fluid-Structure Interaction Modeling by ALE and SPH
Authors: Guo Bao Dong , Qu Qiu Lin , Wu Jia Li , Liu Pei Qing
Published: March 2013

The outcomes of a research focusing on water modeling and Fluid-Structure Interaction by ALE and SPH in LSTC/LS-Dyna971 are presented in this paper. Firstly the water impact behaviors of a rigid wedge are modeled with water region by ALE and SPH. The size of fluid elements plays critical role to the numerical results, so three different cases varied in mesh or particle spacing both in ALE and SPH methods are detailed discussed. The numerical results are compared both one to the others and to the experimental and theoretical results in terms of vertical velocity and slamming force, which can be concluded that the more elements modeled in the simulation, the better approximation with the experiment results. An additional discussion of propagation of pressure wave by SPH and CPU time are also presented.
Low-Diffusion Preconditioning Roe’s Scheme on Simulation of Low-Speed Flows
Authors: Cao Ning
Published: March 2013

Preconditioning technology is an effective method to simulate low Mach number flows, but the stability of the result is poor relatively. With the traditional preconditioning method on Roe’s scheme, the dissipation is too large in the boundary layer and extremely low-speed zone, and sometimes the result is unreasonable. Numerical experiments show the numerical dissipation of the scheme has a notable effect on low-speed flow numerical simulation with preconditioning method. A low-diffusion preconditioning Roe scheme by using an adjustable parameter in preconditioning Roe scheme to control the numerical dissipation and the adjustable parameter value rules are proposed. The low-diffusion preconditioning Roe scheme reflects the real physical dissipation in the extremely low-speed zone. In the region similar to the inflow speed, low-diffusion preconditioning Roe scheme can ensure the stability of the flow field. Numerical results show the efficiency of the new scheme and the low Reynolds number steady solutions of viscous flow past a circular cylinder are satisfied.
Effects of Unforced Bounday Layer Transition on the Performance of a Two-Dimensional Hypersonic Inlet
Authors: Miao Hai Feng , Xie Lv Rong , Chai Weng Xiao
Published: March 2013

Numerical investigation was conducted on a typical two-dimensional hypersonic inlet to study the influence of unforced boundary layer transition affected by compression ramp geometric parameters on the inlet performance. The numerical results show that the transition onset location on the compression ramp can be delayed by filleting the ramp intersection, and also the inlet's performance obviously improves when the transition onset location is delayed. Compared with full turbulent situation, when the boundary layer transition occurs, the unstart of the inlet is significantly mitigated, the heat transfer rate on the compression ramp decreases, both the total pressure recovery coefficient and mass flow rate increase at both design and off-design points. But the static pressure distribution along the ramp is fairly independent of the varieties of boundary layer.
Lattice Boltzmann Simulation of Effect of Rolling Manipulation of Traditional Chinese Massage on Blood Flow
Authors: Tan Hui Li , Kong Fan Rong , Bai Ke Zhao , Kong Ling Jiang
Published: March 2013

A 2D Lattice Boltzmann model for a blood vesssel under rolling manipulation(RM) was presented. The influence of rolling frequency and stenosis coefficient on blood flux, wall shear stress and flow velocity was given by the numerical simulation based on lattice Boltzmann method . It is found that increasing RM frequency can not always increase the flux. There is a proper RM frequency for maximum flux.When the maximum stenosis coefficient increases,the change range of flux and wall shear stress will increase. The rolling massage can also change flow velocity in different sections of blood vessel.
Ghost Cell Immersed Boundary Method for Simulating Flow over Two Circular Cylinders in Tandem Arrangement
Authors: Song Li Wei , Wu Song Ping
Published: March 2013

In this work, a ghost cell immersed boundary method is applied to the numerical simulation of a uniform flows over a circular cylinder and two circular cylinders in tandem arrangement. The Navier-Stokes equations are solved using an implicit fractional step method employed on collocated arrangement variables. Immersed boundary method permit the use of structured Cartesian meshes to simulate flows involving complex boundaries. The shedding of vortices and flow interference between two circular cylinders in tandem arrangement are investigated numerically. The calculations are validated against the experimental and numerical results obtained by other researchers to prove the accuracy and effectiveness.
An Easy Calculation Method on Sweep Efficiency of Chemical Flooding
Authors: Yuan Fu Qing , Li Zhen Quan
Published: March 2013

According to the geological parameters of Shengli Oilfield, sweep efficiency of chemical flooding was analyzed according to injection volume, injection-production parameters of polymer flooding or surfactant-polymer compound flooding. The orthogonal design method was employed to select the important factors influencing on expanding sweep efficiency by chemical flooding. Numerical simulation method was utilized to analyze oil recovery and sweep efficiency of different flooding methods, such as water flooding, polymer flooding and surfactant-polymer compound flooding. Finally, two easy calculation models were established to calculate the expanding degree of sweep efficiency by polymer flooding or SP compound flooding than water flooding. The models were presented as the relationships between geological parameters, such as effective thickness, oil viscosity, porosity and permeability, and fluid parameters, such as polymer-solution viscosity and oil-water interfacial tension. The precision of the two models was high enough to predict sweep efficiency of polymer flooding or SP compound flooding.
A Two-Phase Hydrodynamic Model for Transport Pipelines in Vacuum Sewer Systems
Authors: Li Min , Tang Yong Chao , Li Jian Jun , Meng Pan Pan
Published: March 2013

Intermittent gas-liquid flow with an unsteady, intermittent and high-pressure drop nature is common in vacuum transport pipelines. The characteristics of intermittent flow in vacuum pipelines were analyzed. A one-dimensional transient hydrodynamic model for two-phase transport of vacuum pipelines, which consists of the film model, the liquid slug model and the mix vortex model was deduced for the first time. The model outlines the relationship between hydrodynamic parameters and presents the calculation method of pressure drop, which would be helpful to uncover the transport mechanism of vacuum pipelines and propose a more seemly system design and simulation method for availability, reliability and energy-saving considerations.
Linear Instability Analysis of Confined Compressible Boundary/Mixing Layers Flow
Authors: Liu Zhi Yong , Yuan Xiang Jiang
Published: March 2013

A compressible supersonic confluent flow composed of boundary layers and mixing layers are studied by linear stability theory. The flow is confined in a two-dimensional adiabatic channel. A slower flow lying in the center mixes with faster boundary layer flows on both sides and two mixing layers are evolved near the centerline. Different unstable modes were discovered and the first mode was found to be most unstable. Three-dimensional disturbances were investigated and comparison of instability features was made with unconfined boundary layer flows. The investigation of different slow flow widths was also made and a smaller spacing between the boundary layer and mixing layer was found to suppress the growth of disturbance.
Stress Analysis of Transmission System and Blade for Offshore Wind Power Generator
Authors: Huang Kuo Yi , Tsai Gwo Chung , Li Wei Shiue
Published: March 2013

This article will perform the stress analysis of transmission system and tower of offshore wind power generator . It first utilizes the computer engineering software GH Bladed to get the load on the offshore wind power generator, then ANSYS software is used to get the stress distribution in the structure. From the analytical results, the stress distribution in the structure can be a basic data to perform a new design or strengthen the structure.
Numerical Simulation of the Micromixing Induced by Ultrasonic Vibration of Sidewall-Trapped Microbubbles
Authors: Zheng Su Xia , Su Liang Yao , Li Chun Hui , Xu Zhong Bin
Published: March 2013

It exist several strategies to mix two fluids in a micro channel. The way micro bubble vibrations influence the mixing flow is still unknown. This paper presents numerical simulations of the mixing within the micro device with and without micro bubble vibrations. A simplified model of the microchannel has been successfully employed, via using moving panels instead of sidewall-trapped bubbles oscillation. The simulation method, which exerted sinusoidal movements on the panels to approximately represent the ultrasonic vibrations of microbubbles, has been used to fully solve the Navier-Stokes equations. The comparison between simulations and previously reported experiments, in terms of flow pattern and the mixing performance within micro channel, exhibits a very good agreement. When ultrasonic vibrations of a frequency of 80 kHz and amplitude of 8 μm were applied, the mixing flow patterns have been reproduced and with a little differences comparing to the experimental results. All of these studies have revealed the mix mechanism under the micrometer scale in a certain way.
Study on Optimization of Evaporative Condenser Nozzle with CFD Method
Authors: Zhao Yue , Zhou Hong Jian , Xie Jing , Tang Yi , Miao Chen
Published: March 2013

In the evaporative condenser, the shape and structure of the nozzle determines the spraying effect, which affects the overall heat transfer performance of the evaporative condenser. Due to the constraints of its structure, spraying test is difficult in evaporative condenser operation process. The performance of the two types of nozzle spray is simulated by CFD numerical calculation software, using the two-dimensional modeling. The results show that the two-tier shunt platform nozzle sprays more uniformly, the movement of airflow around is relative more regular, the performance of spraying water is more stable. The reference is provided to select the optimal structure of the nozzle under certain conditions.
Based on the Numerical Simulation of Random Aggregate Concrete Model of the Penetration of the Two Material Models
Authors: Zhao Rui , Yao Yong , Deng Yong Jun
Published: March 2013

Based on the micromechanics principle, establish concrete random aggregate, constitutive model choose HJC model and K&C model, numerical Simulation for the part of the S.J.Hanchak projectile penetrating into concrete targets test. Through the bullets remaining projectile velocity and target plate failure compared, it is concluded that Concrete mesostructure uneven impact of its macro mechanics; flaking and spallation phenomena on the HJC model simulation of the target body front and back by the impact appears less effective, and K&C model is in good agreement with the experimental conditions; K&C model is a simple and effective way to predict the dynamic response of the projectile penetrating into concrete targets.
Optimization Research on the Geometrical Parameters of PDC Core Bits Based on ANSYS
Authors: Qu Jun Li , Liu Xiang Dong
Published: March 2013

The fore-angle and the lateral-rotation angle of PDC core bits, which are two main geometric parameters, have an important influence on the cutting efficiency and performance. Previous studies determined the ranges of two angles mainly depending on the effect of broken rock rather than its mechanical strength to examine the issue. Based on the strength factors, the paper uses finite element program ANSYS to optimize the fore-angle and the lateral-rotation angle of PDC cutters. The main geometric parameters are optimized and the optimal values are obtained under different circumstances, which provides a theoretical basis for reasonable design of the PDC core bits.
Online Adaptive Fuzzy Neural Identification of a Piezoelectric Tube Actuator System
Authors: Yang Da Lin , Yang Wei Dong , Zhang Zhu
Published: March 2013

A coupled actuator-flap-circuit system model and its online identification are presented. The coupled system consists of a piezoelectric tube actuator, a trailing-edge flap, and a series R-L-C circuit. The properties of the coupled system are examined using a Mach-scaled rotor simulation on hovering state. According to the high nonlinear hysteretic characteristics of the coupled system, the generalized dynamic fuzzy neural networks (GD-FNN) implementing Takagi-Sugeno-Kang (TSK) fuzzy systems based on extended ellipsoidal radial basis function (EBF) neural network is used to identify the coupled system. The structures and parameters are adaptive adjusted during the learning process, and don’t need too much expert experiences. Simulation studies show that the piezoelectric tube actuator has high authority with a broad frequency bandwidth, satisfies the requirements for helicopter vibration reduction; GD-FNN has a high learning speed, the final networks have a parsimonious network structure and generalize well, possessing broad application prospects in the helicopter vibration reduction.
Aeroelasticity Analysis of Rotor Using Dynamics of Multibody Systems
Authors: Yu Zhi Hao , Yang Wei Dong , Wu Jie
Published: March 2013

An aeroelastic model and its simulation method of a rotor system are presented. The aeroelastic mode of a rotor is deduced using the multibody system dynamics. The motion equations of the components of rotor system are independent by using Lagrange’s multiplier method, and the differential and algebraic equations are obtained. Equations of the component including joints are deduced to simplify constraint. The angular constraint equations, expressed by Rodriguez parameters, are modified by introducing a nominal motion to avoid singularities caused by large rotations. A large deformation blade component is incorporated. According to the nonlinear implicit expression and high stiffness ratio of the system equations, an implicit integration algorithm combined with the Broyden method is developed, which exhibits excellent numerical stability and good computational efficiency without calculating the Jacobian matrices and their inverse matrices. To verify the validity of the developed method, the transient analysis and aeroelastic analysis of model rotors are imple-mented. The influence of the stability analysis methods, blade structure models on computation is also studied. It demonstrates that the developed method is useful for improving the computation precision of aeroelastic analysis.
Homoclinic Tangencies for a Rotor-Active Magnetic Bearings System
Authors: Yang Feng Hong , Tong Hong Zhi
Published: March 2013

The homoclinic tangency for a rotor-active magnetic bearings (AMB) system with the time-varying stiffness are considered in this paper. The zeros of Melnikov equation are paid more attentions and a 3-order zero was gained and some numerical results under the parameter perturbations were shown.