bluuebunny/crossref_metadata_2025 huggingface dataset:
Intelligent PID Control and the Bifucation Behavior of Hydrogenerator Set
Authors: Liao Zhong , Song Chun Dan
Published: February 2014

. Considering of the highly nonlinear, time-variable and complex dynamics and the easy variance of hydrogenerator set systems structure and parameters, a nonlinear dynamical model is presented, which can be analyzed by the bifurcation theory of nonlinear differential equations and simulated in computer. By using the genetic algorithm, the PID parameters of hydrogenerator set intelligent system are optimized and the control performances are improved. The algebra criterion about the existence of bifurcation is employed to study the bifurcation behavior of the nonlinear model which takes the PID parameters as the bifurcation ones. The simulations show that a supercritical bifurcation is likely to exist in hydrogenerator set system and the bifurcation will occur for the higher values of PID parameters. Theory and simulation results of this paper can be considered as good suggest for intelligent PID control system of hydrogenerator set system.
Dynamic Characteristic Analysis of Transmission Tower
Authors: Xie Xiang Zan , Wei Ke Lun
Published: February 2014

Transmission tower is a widely used higher order statically indeterminate spatial structure, as the pillar of power transmission, modern society are increasingly concerned about its safety and reliability. This paper establishes a large-scale three-dimensional space model of transmission tower by using the finite element method, calculate and analyse the first six vibration modes and frequencies of this transmission tower, study the characteristics of each order vibration mode. These research results provide some references of design for the large-scale transmission tower.
Planning of Terminal Unit Amount in Distribution Automation Systems
Authors: Zhang Kun , Zhao Jian Wei
Published: February 2014

To help with the planning and design of distribution automation systems (DASs), the best amount of terminal units (TUs) mounted in a DAS is analyzed from the perspective of benefit/cost ratio first. From the perspective of reliability, the amount of various kinds of TUs in different situations is studied, that is only TUs with tele-control function, only TUs without tele-control function, a hybrid of TUs with tele-control function and TUs without tele-control function. Some circuit breakers with current protection mounted on some branches arc investigated at length. The following conclusions arc drawn that only one TU for each feeder is the best choice from the viewpoint of benefit/cost ratio, and that the demanded amount of various kinds of TUs depends on the reliability performance desired, the time of isolating the fault section by manual operation, the time of reparation, and the frequency of failure per-year. A DAS planning example with 220 feeders is given to illustrate the proposed methodology.
Grid-Connected Control Strategy Based on Fixed Mi Coefficient for Single-Phase Photovoltaic System
Authors: Zhu Wen Jie , Rong Fei , Luo An , Xu Yong , Hu An Ping
Published: February 2014

This paper presents a grid-connected control strategy for single-phase photovoltaic (PV) system. Voltage source inverter (VSI) of a PV system is a core component which will produce some harmonics when the switch is operated between on and off continuously. To suppress harmonic distortion in the VSI output current, a fixed modulation index (MI) control loop based on PI controller is added to the traditional double closed-loop. The proposed method can fix the MI coefficient to be a large value in any conditions. The design of the controller and the stability of the grid-connected system are discussed in detail. Simulation and experiment results are presented to demonstrate the dynamic and precision performance of the controller for harmonic suppression when the proposed PV system is connected to the grid.
Linear Regression for Forecasting Photovoltaic Power Generation
Authors: Guo Hua Ping , Wu Shuang Hui , Wang Zhao Qing , Wu Chang An
Published: February 2014

One key issue for knowledge discovery is to build a model with simple structure, high performance and interpretability. Linear regression is simple and interpretable model comparing to other models such as neural network. This paper introduces linear regression into photovoltaic power forecasting. Experimental results on the data set collected by Zhongwei third photovoltaic power station of Ningxia Jinyang new energy Co., Ltd. show that, compared with neural network, linear regression performs better generated power forecasting.
The Summarization of Fault Line Selection of Small Current Grounding System
Authors: Zhang Zhi Xia , Wang Zhi Lei , Li Kun
Published: February 2014

With the development of power technology and the improvement of reliability of power supply of power user requirement, small current grounding system become the main grounding mode of distribution network. Small current grounding power system fault line selection is always one of the puzzles in medium voltage distribution network relay protection technology, until now it has not been solved satisfactorily. In this paper, we summary and review the algorithms of small current fault line selection, review domestic and abroad extensive works and achievements in this field in recent years. Summarizing the fault line selection methods based on the steady state information and transient information and analyzing the advantages and disadvantages of various algorithms, at the same time, we study the difficulties of future research and the directions of research.
Research on Generator Tripping Value of Security and Stability Control
Authors: Zheng Hui Ping , Yang Yu Long , Song Shu Yong , Liu Xin Yuan , Xue Min , Zhang Wen Chao
Published: February 2014

In this paper, the problem of the excessive generator tripping value of security and stability control after occurrence of the N-2 fault in the Shentou-Yantong transmission line of Shanxi DaTong Regional grid is studied. And the principle of security and stability control measures based on equal area criterion is analyzed. The reason leading to excessive generator-tripping value of security and stability control after the occurrence of the N-2 fault in Shentou-Yantong region is figured out, and it is that the steady-state stability limit of transmission section decreases and the accelerator power cannot be released. Finally, the results of theoretical analysis are verified by simulations. The simulation results indicate that too large generator-tripping value of security and stability control is mainly caused by decrease of the steady-state stability limit of the transmission section after occurrence of the fault in Datong. The conclusions in the paper have referential significance for the study on similar power concentrated send-out systems.
Research on Admittance Model of Primary Electricity Equipments Based on LCC
Authors: Chen Fa Chi , Song Xiao Nan , Zhang Bin , Zhou Rong Lin
Published: February 2014

Because of the unsatisfied present situation of bidding evaluation in the field of electric power equipment, the LCC theory is introduced into the bidding evaluation method, which can be used to evaluate the total cost of electric power equipment. Combining with ADC method, the paper proposes a comprehensive procurement model and verifies it by a practical case.
Maximum Wind Energy Capturing of Wind Turbine Generator Based on Adaptive Inverse Controller
Authors: Wang Wan Zhao , Wang Jie
Published: February 2014

The variable speed wind turbine generator exhibits serious nonlinearity, uncertainty and difficulty accurate modeling, conventional PID controller can't achieve ideal control effect. In this paper, an adaptive inverse control scheme based on neural network identification technology is proposed to solve the above problem. The scheme firstly uses online identification of one DRNN to obtain the Jacobian information of plant. On this basis, another DRNN identifies the inverse plant model which constitutes adaptive inverse control system as controller. The simulation results verify that the adaptive inverse control scheme has excellent adaptability and robustness, which can make the actual rotational speed of wind turbine rapidly track the set point to maintain the best tip-speed ratio in order to get maximum wind energy capture in the random wind conditions.
Application of Average Filtering Algorithm in High Voltage Grid for Pulse Shocking
Authors: Sui Tao , Kong Zhen , Kong Wei Wei , Lu Wu , Guo Yang
Published: February 2014

In order to increase the performance of the current high voltage grid for pulse shocking, which is imperfection in controlling the intensity of pulse shock in the high voltages, a set of perimeter prevention high-voltage grid system is design with using the programmable logic controller (PLC). In this design, the average filtering algorithm is applied for promoting the accuracy of the intensity. The feasibility of the algorithm is verified through simulation. In this paper, the algorithm and the experimental procedure are mainly discusses, and so get some result about the changeable resistor, which could adjust the intensity of high voltage pulse shock.
Efficiency Enhancement of Novel Photovoltaic-Thermal (PVT) Air Collector
Authors: Tsai Huan Liang , Hsu Chieh Yen , Chen Yung Chou
Published: February 2014

This paper presents the efficiency enhancement for a novel photovoltaic/thermal (PVT) air collector in which PV and thermal efficiency is simultaneously enhanced with a reciprocal aid. With the encapsulation of solar cells directly on a fin-type heat sink, the direct conduction mechanism and the convective area for the thermal transportation are effectively increased. Through a two-month experiment measurement, it is found that the thermal efficiency of PVT module is obviously enhanced up to over 50% in sunny days. In addition, the waste heat recovery decreases the operating temperature of solar cells and concurrently improves the PV efficiency. The results demonstrate the concurrent enhancement of the novel PVT module in PV electricity and solar thermal efficiency.
Optimal Reactive Power Dispatch Based on Mixed Bacterial Chemotaxis Algorithm
Authors: Zhang Xiao Ying , Li Chen , Li Zhen
Published: February 2014

Particle Swarm Optimization (PSO) algorithm converges fast but it is easy to fall into local optimum, and bacterial chemotaxis (BC) algorithm prevents premature convergence and prevents falling into local optimum, so a new mixed bacterial chemotaxis (MBC) algorithm is proposed by combining the PSO with BC. The novel algorithm is applied to reactive power optimization on power system. First the PSO is used to find best solution, then BC is used to find the optimal solution among the selected area of previous step, the reserving elite strategy is introduced to enhance the efficiency of the algorithm, and then the optimal solution is obtained. Through the comparison with PSO and BCC in the reactive power optimization of IEEE30-bus system, the results indicate that MBC not only prevents premature convergence to a large extent, but also keeps a more rapid convergence rate than PSO and BCC.
Static Var Generator Technology and its Applications
Authors: Guan Zheng Qiang , Liu Si Jing , Liu Xing Hua
Published: February 2014

This paper analyzed the principles, the control methods, the features of the three operational patterns, and the merits of SVG technology as well as a brief introduction to the latest applications of SVG technology. Due to the limitations of the SVG technology, meanwhile its control strategies are very complicated; its fabrication cost is comparatively high when used to for the middle and high electricity pressure and big capacities of electricity transmission. But with the wide use of new technologies and new materials, the SVG technology will surely finds its broad applications.
Research on Power User Electrical Energy Data Acquire System Based on Micro-Power Wireless Technology
Authors: Sun Li Li , Lu Xin , He Ye Shen
Published: February 2014

Currently, micro-power wireless communication technology used in power user electrical energy data acquire system have some problems such as transport distance, power, data rate, antenna length, interaction (standard), deployment environment, stray radiation and so on. This paper proposed a micro-power wireless communication module which meets the State Grid Corporation of China Enterprise Standard Q/GDW 1374.3-2013 was designed by the author,and the key technology and major problems were researched and analyzed.
Design of the Wireless Communications System in the Nuclear Power Plants
Authors: Gao Xiao Yan
Published: February 2014

With the development of wireless network technology, wireless communication is widely used in entertainment, business, factory and other fields. But, for those nuclear power plants which are currently in service, wireless technology did not get fully used, some even in unused condition. Actually, wireless communication system can be used to provide wireless connection between computer and mobile/portable devices, and provide access to LAN system; it also can be used to transmit video and data for cameras and sensors; it can realize wireless expansion of MAIN PABX system, so to meet all kinds of Wireless communication requirements in Nuclear Power Station.
Research on the Evaluation of China’s Automotive Industry Security: Based on Gray Model
Authors: He Wei Da , Pan Zheng Rong
Published: February 2014

In this paper, safety evaluation index system was made up on the automotive industry, and we make evaluation of 2001-2011 automotive industry safety by the method of gray model, The research indicates that China automotive industry has been in a basic safe condition, which shows it is in a positive trend. Nevertheless, the range of the development of industry by which the competitiveness index measured was too large, which means the development of automotive industry was to a much extent affected by related policies developed by government, the market is not rational. The researchers also indicate the major reason of the Less competitive of Chinese automotive industry and over-rely on the export, which is low R&D investment and lack of key production technology. The conclusion of this article plays a role of guidance for government to promote effective automotive industry development policy.
Study on the Dynamic Characteristics of Hot-Film Flow Sensor Based on the Sampling Air Channel
Authors: Liu Wei , Zhao Li Feng
Published: February 2014

The hot-film flow sensors accurately measure the intake flow of engine. The air flow in the engine intake manifold is typical unsteady flow whose flow velocity changes remarkably. Therefore, the flow sensor should have a faster dynamic response characteristic. A thermosetting coupling model of a hot-film sensor was established based on CFD which is used to simulate dynamic response characteristics; the temperature field of the hot-film flow sensor probe was simulated. In addition, the dynamic response characteristics of the sensor simulated using the step pulse, and tested the dynamic response characteristics based on flow test equipment.
Research on Electric Vehicle Charging & Battery Swapping Robot System
Authors: Wang Xin , Wang Jing
Published: February 2014

Electric Vehicle will be the main trend of automotive industry in the future. The purpose of the scheme is to provide electric vehicle charging & battery swapping robot system based on palletizing robot for solving the double pressure of resources and environment problems. In this paper, the battery swapping robot is the key of the system, and will be mainly discussed from the mechanical body and electrical control part in detail. Experiments show that the positioning precision during the battery swapping process is high, the relative displacement is small, the position is accuracy, and the swapping speed is moderate.
Analysis of Influence Factors on Braking Energy Recovery of Pure Electric Vehicle
Authors: Cai Jian Wei , Chu Liang , Wei Wen Ruo , Zhang Yong Sheng , Li Wen Hui
Published: February 2014

Based on the analysis the theoretical of regenerative braking and energy flow of the pure electric vehicle, the main influence factors of braking energy recovery were obtained. Ignoring the energy loss and the efficiency of system components as well as the response delay of the hydraulic braking system, two different regenerative braking control strategies were established without regard to the braking force distribution restrictions of the relevant brake laws. The simulation model was built on MATLAB/Simulink platform to analysis the effect of control strategies, vehicle mass and driving cycle for pure electric vehicle braking energy recovery. It was guidance for the development of pure electric vehicle braking energy recovery control strategy.
Optimal Torque Distribution Strategy of Hybrid Electric Bus Based on Genetic Algorithms
Authors: Liu Cui , Gao Xiu Hua , Guo Jian Hua
Published: February 2014

In this paper, the Hybrid Electric Bus (HEB) equipped with Compressed Natural Gas (CNG) engine is taken as the research object on the basis of logic threshold control strategy and the Genetic Algorithm (GA) is adopted to optimize the HEB control thresholds at a typical operating condition of a Chinese city bus. The simulation results show that the overall efficiency of GA optimize is higher than the original control thresholds, the engine operating point moves to the high efficiency region which can be considered optimal threshold by GA makes the overall efficiency has been effectively improved, so as to achieve without lowering the vehicle dynamics and SOC balance of the premise, the gas consumption decreased and increased HEV economy.
The Study of Automatically Leveling Control System on Electromechanical Vehicle Stable Platform
Authors: Jiao Ruo Bing , Chen Chong , Yuan Min , Wang Fu Ping
Published: February 2014

This paper had developed a four-point supporting automatic leveling system on electromechanical vehicle platform. According to the method fixed the center point for leveling, modular design of the system was adopted, so the system had a good portability. The system has not only good performance on leveling time shorted but also high leveling accuracy and high reliability. So it meets the requirements.
Design and Implementation of the Disassembly and Assembly Equipment to the Buffer Braking Device of the Elevating Mechanism of the Heavy Caliber Ground Artillery
Authors: Jiang Wei , Li Ning , Zhu Jian Feng , Zhang Meng , Chen Liang Ming
Published: February 2014

Through the advanced hydraulic control technology to solve many disadvantages of the present disassembly and assembly equipment of the buffer braking device, and the new disassembly and assembly equipment of the buffer braking device of the elevating mechanism of the heavy caliber ground artillery is designed, and it has a very important significance to improve the maintenance support efficiency of the equipment.
The Experimental Study on the Enhanced Evaporating Property of the Pineapple Juice by Ultrasound
Authors: Song Ji Tian , Xu Xiao Fei , Tian Wei , Liu Jian Bo , Zhao Zheng
Published: February 2014

In this paper, the heat transfer of pineapple juice was investigated on a new evaporator with ultrasound. The effects of various factors on the heat transfer coefficient were analyzed, including feed rate, evaporating temperature, temperature difference of heat transfer, and juice concentration. The proposals of design and operation for this new evaporation were also discussed.
Research on Temperature Distribution and Stress Distribution Model of Prefabricate Block Electric Furnace Roof
Authors: Li Xin Can
Published: February 2014

Electric furnace roof is an important device for electric steel making, whose heat preservation performance and life-span have a direct impact on the economic benefits of iron and steel enterprise. Considered contact behavior between prefabricate block, this paper establishes the complete CAD/CAE model of the electric furnace roof with finite element software based on the theory of transferring heating subject, and respectively calculates the stable temperature and stress field of the firebrick roof and the prefabricate block roof in last melting stage, as is advantageous to analyze the level and the distribution of temperature and stress of electric furnace roof.
Preliminary Exploration of the Dynamic Model and Experiment on an Impact between a Tennis Ball and Racket
Authors: Hong Hui Hui , Han Liang
Published: February 2014

The research on an impact between a tennis ball and racket is very significant to improve the level of tennis and reduce the sports injuries. A preliminary study on an impact between a tennis ball and racket is carried out in this paper. It is composed of four parts: the reference of the existed dynamic model, the experimental set-up, the test system, the collection and analysis of experimental data. The preliminary experimental results are compared with the dynamic model, and the impact dynamic model can be improved after considering every effect on the impact. The preliminary results show that the model can be used to predict the tennis impact on the racket with different inbound velocity.
RETRACTED: Structure Optimization of Agricultural Vehicle Frame Based on APDL
Authors: Xiang Fei Fei , Xiang Zhong Ke , Nie Qiu Xiang
Published: February 2014

Retracted article: This paper is about structure optimization of agricultural vehicle frame which adopts the method of adding strengthen box ,set up Frame and strengthen box parameterized mode Based on APDL , Using the optimization module of ANSYS to optimize the shape of the box and place got obvious improvement to the bad stress of longitudinal beam,Thus the overall performance of the frame is improved.
Force Analysis of the Anchor Chains and the Cable in the Crane-System with a Floating Base in Regular Waves
Authors: Huang Ya Xin , Wang Bing , Liu Jun Yi
Published: February 2014

In order to analyze the force of the anchor chains and the cable in the crane-system with a floating base, firstly the system is simplified to two-rigid-body model and the anchor chains in the system are in symmetric layout; then the motion response of the system as well as the force of the anchor chains and the cable are solved by use of discrete time transfer matrix method, lastly the time history curves of motion of the system and the force of the anchor chains and the cable are obtained. The results of numerical simulation show that the roll motion has greater influences on the system comparing with sway and heave, the amplitudes of sway and heave are small. Furthermore, the force of the anchor chains are mainly caused by the roll motion while the force caused by sway and heave are relatively small.
The Finite Element Analysis of the Stress and Deformation of the Micro-Milling Cutter Based on ANSYS
Authors: Wang Xin Xin , Lu Xiao Hong , Xu Guang Hao , Wang Feng Chen
Published: February 2014

Because of the differences in spindle speed and extended length of micro milling cutter, Tool life and machining surface quality vary markedly. Therefore, a geometric model of carbide end mill whose diameter is 0.2mm is built. With free meshing method, meshing density is set up reasonably, which ensure the rationality of the built finite element model. On the premise of considering the extended length of the micro milling cutter, apply linear load on the main cutting edge and front-cutting edge, carry out the deformation and stress analysis using finite element software. Applying different spindle speeds under four extended lengths, through comparing maximum stress and strain under four extended lengths, change rules are summarized and the extended lengths of the tool suited for micro-milling are achieved.
Reliability and Failure Analysis of CNC Machine Based on Element Action
Authors: Zhang Gen Bao , Zhang Lian , Ran Yan
Published: February 2014

Since the element action (e-action) is the smallest motion unit in realizing systems function, its reliability plays an important role in system operating ability. In this paper, a new method of CNC machines reliability analysis based on e-action is proposed. Firstly, the definition of e-action reliability is studied and the mathematical model is built. Then the methodology of FMECA based on e-action is introduced. Finally the grinding carriage feed movement is taken as an example to illustrate the methodology.
The Research on Computer Aided Design Combined with Product Design
Authors: Tian Wei
Published: February 2014

Industrial design is an emerging edge science, which intersperses throughout the development, production and sales of product. From market research to data reduction and then to the final market launch, every segment permeates computer aided design, which will develop towards to digitization, networked, virtualization, intelligent inevitably.
Research of Gantry Machining Center Assembly Deviation Sensitivity Based on Multi-Body System
Authors: An Guo Ping , Liu Zhuang Zhuang , Liu Zhifeng , Zhao Yong Sheng , Cai Li Gang
Published: February 2014

Heavy duty machine tool has some special points, such as large size, complex structure, long cycle at Installation and commissioning, high requirements assembly processes and so on. Therefore, this paper established a mathematical model to transform the origin parts of the gantry machining center into assembly special form and creates a software as a plug-in for Solidworks based on it, proposes an easy but very practical assembly method based on Multi-body system under virtual environment. This method can calculate assembly deviation caused by manufacturing tolerance very quickly, and bring the sensitivity information clearly. Assembly deviation sensitivity and assembly method proposed in this paper can provide a way for the virtual assembly of heavy-duty CNC machine tools, Thus provide an important theoretical basis to improve the performance of the machine
Bolt Static Finite Element Numerical Simulation and Experimental Research
Authors: Dong Zheng Yan , Zhang Han Long
Published: February 2014

This study investigated the wind turbine blade root bolt static strength using the full scale static test, selected the root bolts of 1/4 bridge strain gauge using the finite element analysis method and the dynamic and static strain instrument. The data of the stress loading combined tension and bending bolt were obtained.
Study on Damage Ability of Anti-Armor Composite Warhead
Authors: Lu Hai Tao , Li Wei Bing , Wang Xiao Ming , Li Wen Bin , Chen Chun
Published: February 2014

To improve the damage ability of the hollow-charge warhead, and the utilization of the dynamite, added the prefabricated fragments at the circumferential of the shaped warhead, used the finite element software to calculate the influence of different prefabricated fragments, different shell structure on warhead's EFP and fragments performance, and also the penetration capability of them. The results show that: the performance of the damage elements formed by this anti-armor composite warhead are very well, it can damage the armored vehicles, ships and other targets, the sphere fragment can penetrate 12mm thick armor steel in 60m, and damage personnel in the 240m, EFP can penetrate the armor steel more than 0.5 times of the charge's diameter, this research can provide reference for the further research on multi-using warhead.
Primary Research on Processing Method of Elliptic Workpieces
Authors: Wang Wen Hong , Jiang Yu
Published: February 2014

to solve the difficulties like locating and clamping in the processing of elliptic workpieces and meet the requirements of processing, so as to achieve the final processing purpose. Therefore, the characters of the parts and the best performance of current machining tool are combined, and the mandrel platform with included angle of 45° is prepared on condition that the processing difficulties and requirements are fully understood, and the locating and clamping are achieved by compressing the nuts, then the four-corner chuck is used for alignment and turning, so as to meet the requirements for production.
Numerical Simulation of Thrust Vector Control for a 2D Nozzle
Authors: Wang Bo , An Yu Ge , Zhang Man , Zheng Yuan
Published: February 2014

In modern campaign, Aircraft maneuverability and agility have been playing an increasingly important role. Plasma thrust vector control can avoid shortcomings of traditional methods, it has a very good prospect.In present work a CFD simulation of a thrust vector control for a 2D nozzle is performed.The results showed that the change of the magnetic field can impress the vector turn of the nozzle flowfield.
Study on the Hole-Wedge Effect of Friction Pair
Authors: Han Zhi Hong , Liu Shu Yang
Published: February 2014

The self-circulating compensation of lubrication was modeled ,a ferrofluid microcirculating trust bearing was designed,which showed that: the self-circulation compensation of colloidal lubrication can improve the tribological performance significantly.
Investigation on the Sheet Metal Anisotropy by the Plane Strain Compression Method with Laminated Samples
Authors: Tian Hao Bin , Liu Xiao Hang , Yuan Wen Jing , Li Xue Lei
Published: February 2014

In order to obtain the sheet metal anisotropy under wide strain range, plane strain compression method with laminated samples is investigated. In the experiments, two laminated samples are introduced, sample 1 is deformed at rolling and thickness direction, and sample 2 is deformed at rolling and transverse direction. In the paper, the ratio of deformation forces obtained from sample 2 (p2 ) to sample1( p1) is used to assess the anisotropy of sheet metal, and verified by analytical method. The results show that the ratio of p2top1 is the function of anisotropic index r, and the anisotropic assessment by this method has a good agreement with that obtained by universal uniaxial tensile test at uniform deformation.
The Statics Analysis of the Lathe Tool Based on Workbench
Authors: Cheng Zheng Yong , Gu Wen Juan , Zhang Xiao Hui , He Bang Gui , Li Ying
Published: February 2014

The 3D model of the lathe tool is established by using the Pro/E of 3D design software, then imported 3D model into the finite element software Workbench, and analyzed its statics using the finite element method, and got the stress figure and strain figure and total deformation figure while the lathe tool undertaking the cutting force, through the analysis it shows that the strength of the lathe tool can meet the processing requirements.
Study on the Deformation Resistance of Tension-Reduction Process of Steel Pipe
Authors: Zhang Fang Ping , Lai Fei , Ren Zhi Feng , Gui Hai Lian , Zhao Chun Jiang , Sun Bin Yu
Published: February 2014

Plastic deformation resistance is a basic parameter of mechanics parameters in press work theory and technology. In this paper, the influencing factors of deformation resistance are analyzed and the model of deformation resistance is established. The deformation resistance can be calculated by program with Lagrange interpolation method. This result provides evidence for calculating mechanics parameters and designing metalworking equipment.
Stress Intensity Factor Solutions of Integral Stiffened Panels Based on an Improved Displacement Compatibility Method
Authors: Guo Xiang , Liu Jian Zhong , Zhao Yan Guang , Shang De Guang , Liu Hu
Published: February 2014

Stiffnend panels are used to investigate the fracture behavior of the fuselage components within the framework of the damage tolerance analysis. Integral structure are gradually replace butilt-up structure in recent years. This paper presents an improved method based on displacement compatibility principle to calculate stress intensity factors. A finite element method based on intgral contour is introduced and used for verifying the solutions. Stress intensity factor solutions of built-up structure and integral structure were both calculated using these two methods. From the comparison, these two solutions are in good agreement both in built-up structure and integral structure.
Thermal Stress Analysis of Rotor of Ultra Supercritical Steam Turbine
Authors: Zhao Xiao Tong , He Qing , Du Dong Mei
Published: February 2014

The rotor of ultra supercritical steam turbine runs in bad condition with high parameters of steam. The large heat stress of rotor may appear when the operating conditions of turbine unit is changed, for example, adjusting load to meet the requirements of peak and valley of grid, especially, improper operation causing serious damage to rotor. According to theory of thermal stress analysis, first, the steam parameters and their heat transfer coefficients of all cascades of 1000MW ultra supercritical steam turbine is calculated. Then the temperature field and stress field of the high-pressure rotor in the process of cold startup calculated by the finite element software are analyzed and discussed. The results are important to the startup and changing conditions of 1000MW ultra supercritical steam turbine unit.
The Shaft Designs for a New Type Dispatching Winch
Authors: Gao Hu
Published: February 2014

This project was to design the shafts for a new type dispatching winch, the author has improved much base on the original plan. By adopting involute gear transmission of two-stage NGW type, the transmission pattern has been changed from fixed shaft pattern to moving shaft pattern and the DOF of the mechanism has increased, which has achieved the composite motions between the components and has catered to the target of decelerating.
Simulation and Study on Ride Comfort of Articulated Dump Truck Based on Rigid-Flex Coupling
Authors: Guo Jie
Published: February 2014

For the poor ride comfort performance of the articulated dump truck, the dynamic model of ADT was built and its dynamic characteristics were also studied through finite element and multi-body system dynamic theory. According to the modal neutral file generated by finite element software with the flexible processing, the flexible coupling virtual prototyping model was set up for the multi-body dynamics simulation in ADAMS to obtain and analyze the data about the ADT ride comfort. This paper provided references for the design, redesign and optimization of the ADT.
Contrastive Analysis on Thermal Deformation of Thrust Bearing Pad with Two Kind of Supporting
Authors: Li Yong Hai , Liu Shi Bo , Yao Rong Kui , Wang Jian , Yang Ning , Gao Yan , Yang Jia
Published: February 2014

In order to solve thermal deformation, the finite element numerical simulation of two kind of tilting pad thrust bearing is made for the same pad surface, and thermal deformation is made to analyze comparatively. The results show that the temperature field, the deformation field and the values of pad are similar for two different supported thrust bearing (point, line support) under the same operating condition. The pad temperature and deformation will increase with the increasing of pv values. According to the calculation conditions, the temperature field rose about 1°C, and the thermal deflection increased 0.002mm with pv value increased by 10%.
Envelope to a Two-Parameter Family of Point Vectors Method for Surface Swept by Form Wheel
Authors: Peng Yuan Zhi , He Kun , Li Guo Long , Zhang Wei
Published: February 2014

The form wheel generating curve is always a composited curve which is composed of lines and arcs, and the calculation of the envelope surface is more complex than conventional rotary cutter. Therefore, a method of envelope to a two-parametric family of point vectors is proposed, which defines the point and its normal vector on the wheel generating curve as a point vector. Each point vector corresponds to a virtual ball uniquely. The rotation of point vector forms latitude circle and the valid envelopment movement forms sectional circle. The intersection of latitude circle and sectional circle is grazing point; The analytical calculation model is established, in which the geometry parameters of virtual ball can be directly calculated from point vector; An example is presented to demonstrate the effectiveness of the method which can be used for form grinding geometry simulation, accuracy evaluation and optimization of the wheel path.
Study on the Relationship between Fruit-Stem Separation Force and Fruit Shape of Processing Tomato
Authors: Bi Xin Sheng , Mei Wei Jiang , Zhang Jin
Published: February 2014

In order to provide a theoretical basis for the research on processing tomato harvester, three kinds of processing tomatoes which were largely cultivated and suitable for mechanization harvest in Xinjiang location of China were sampled, and after measuring the red-ripe fruit weight, fruit transverse and longitudinal diameter, the regression equations about the fruit weight and the fruit transverse diameter, fruit longitudinal diameter, fruit shape were established, and the fruit-stem separation force test on the samples was carried out, so the regression equations about the processing tomato fruit-stem separation force and the fruit weight were established. Finally, the mathematical models about fruit-stem separation force and fruit shape of processing tomatoes were built.
Study on Casting Instead of Traditional Forging for Main Shaft of Megawatt Wind Turbine
Authors: Chen Xi , Yang Gang , Yang Yi , Yin De Qiang
Published: February 2014

Turbine main shaft is one of the most important components for wind turbines. Nowadays, the main shafts of megawatt wind turbine have been mainly manufactured by forging technology. Although forged spindle has good performance, forging process is so complicated that it generally takes long production cycle and high cost. This paper has been undertaken in an attempt to describing a novel method of gravity casting to manufacture wind turbine. It has been found that some performances such as the tensile strength and the yield strength of the casted main shaft are higher than those of the forging standard ones, while other performances dependent on various positions of the sampling present different performance distribution.
The Hall Automotive Wheel Speed Sensor and Simulation for its Signal Processing
Authors: Luo Qie Ming
Published: February 2014

The Hall automotive wheel speed sensor and have been studied, based on the its signal characteristic, the signal process circuit model that contains limiter circuitlow pass filter and lagging comparator has been established. The corresponding simulations under the Matlab/Simulink show that the working stability and anti-interference of this circuit can meet the demand of speed signal processing.
Influence of Oil-Returning Slot on Load Capacity of Heavy Constant Flow Hydrostatic Center Rest
Authors: Wu Bo , Huang Zhi , Yu Xiao Dong , Jiang Hui , Wang Chun Zhou
Published: February 2014

In order to increase load capacity of a heavy constant flow hydrostatic center rest, a theoretical study concerning the lubrication performance of the heavy constant flow hydrostatic center rest is described. The Computational Fluid Dynamics and the Finite Volume Method have been used to compute lubrication characteristics, such as the recess pressure and the oil flow state. The influences of oil-returning slot on the load capacity of the heavy constant flow hydrostatic center rest was analyzed based on the computational fluid dynamics and lubrication theory, and the influencing laws were revealed. Through this method, the reasonable data can be provided for optimal design and lubrication performance improving of the constant flow hydrostatic center rest in the heavy equipment.
Finite Element Analysis of a Forklift Truck Mast System
Authors: Zhuang Yuan , Shan Zhong De , Zhang Qian
Published: February 2014

The finite element method (FEM) has been used for an independent analysis of forklift truck components. However, the accuracy of such an analysis may not be reliable because it does not in view of the interaction of the forces transferred between components. Here, we analyze the mast system as a whole using an FEM based on a simulation chain method employing MPC184 units, as well as a method to analyze components independently. Both methods are used to simulate the stress of the upper beam of the inner mast. We then compare the maximum stresses calculated using the two different methods under three sets of working conditions. The data show that, in comparison with theoretical results, the average error rate of the overall analysis method was 4.71%, while that of the independent analysis was 33.3%.
Non-Standard Parts Model Library Based on VIRTOOLS
Authors: Yang Cheng De , Shen Bin , Gu Xin Min , Dong Zi Wei , Tian Zi Qiang
Published: February 2014

With the new equipment research preparation put into use, in order to ensure special purpose forces, in the existence of a large number of new equipment nonstandard parts. These non-standard parts in the various aspects of the new equipment play a great role. This topic-based VIRTOOLS 5.0 software to establish a non-standard parts library in new equipment, new equipment, used to strengthen the management and maintenance of non-standard parts for the maintenance of armed forces provide a solid guarantee. Meanwhile, from the user maintenance reality, virtual assembly of non-standard parts, non-standard parts for the maintenance provide effective protection.
The Bifurcation and Chaotic Characters of an Intelligent Magnetoelectroelastic Thin Plate
Authors: Ren X.J. , Xue C.X.
Published: February 2014

In this paper, an intelligent magnetoelectroelastic thin plate is coupled with a transverse magnetic field and uniformly distributed load. Considering the von Karman plate theory of large deflection and the geometric nonlinearity, the damping Duffing equation is obtained. Using the Melnikov function method, the Chaos condition of the system under the Smale horseshoe transformation is obtained. The bifurcation diagram, the wave diagram of displacement, and the phase diagram are shown here by the numerical analysis. The simulation results show the complex nonlinear vibration characters of the intelligent magneto-electro-elastic thin plate.
Numerical Research of Inlet Temperatures Influence on Combustion Characteristics in Micro Gas Tuebine's Oxygen Enriched Combustor
Authors: Wang Fu Zhen , Liu Shi , Shao Ji Xu , Ren Xiao Chen
Published: February 2014

Keeping exhaust gas temperature constant in oxygen enriched and flue gas circulating Micro Gas Turbine, Numerical Research is carried on to study inlet temperatures influence on combustion characteristics. Simulation shows that along with increase of methanes temperature, combustion efficiency increase slightly, uniformity coefficient of outlet temperature decreases, total pressure recovery coefficient decreases, content of carbon monoxide and methane in outlet gas decrease. However, when inlet methanes temperature exceed 100 °C, content of NOx increase rapidly in flue gas. The simulation result supplied reference for design of oxygen enriched and flue gas circulating combustor.
Dynamic Property Analysis of Damping Rubber in Rail Fastenings under Different Deformation Condition
Authors: Zhang Bin , Luo Yan Yun , Shi Zhi Nan
Published: February 2014

This paper studies the experimental research on dynamic characteristics of the damping rubber in high elastic fastening by the electro-hydraulic servo movement tester. Based on a hypothesis superposition theory of nonlinear elastic restoring force and nonlinear damping force, a non-linear dynamic mechanical model is proposed. The dynamic stiffness and damping parameters of the rubber are obtained in different deformation conditions based on the dynamic mechanical model. The dynamic stiffness is analyzed, and the results show that dynamic stiffness is closely related to excitation frequency and amplitude. Furthermore the dynamic stiffness is analyzed under different free surface of rubber components by using FEM. That also reveals the changeable characteristics and affected factors of the damping rubber of the high elastic fastenings in large distortion condition.
Computer Simulation of the Coupled Analysis of Piston Secondary Motion and EHD Lubrication Based on Flexible Multi-Body Dynamics
Authors: Yang Zhen Yu , Zhang Wei Zheng
Published: February 2014

A coupled model of piston secondary motion and mixed hydrodynamic lubricated was established based on flexible multi-Body dynamics. The model included elastic deformation and roughness of the two surfaces. The effects of rough surface compared to absolutely smooth surface on piston secondary motion mixed lubrication are discussed. The results show that roughness of the surface can make the fluid a better way to lubricate the surface and decrease the secondary motion, but in the high load asperity contact will occur.
Life Evaluation of Electro-Hydraulic Servo Valve Based on Wear Mechanism
Authors: Wang Xiao Hong , Li Qiu Xi , Feng Ya Li
Published: February 2014

Electro-hydraulic servo valve is the key component in electro-hydraulic servo control system, it has high reliable assemblies over a long period of time. This paper utilizes the accelerated degradation testing to evaluate their reliability and life. Firstly, the wear failure mechanism of electro-hydraulic servo valve is analyzed to determine. Then, by modeling the degradation process as a drift Brown Motion, this paper generated the reliability model of the electro-hydraulic servo valve. Finally, the maximum likelihood is used to estimate the degradation data of leakage from the test. The methodology in this paper is demonstrated and validated by reasonability of estimation of electro-hydraulic servo valve.
Dynamics Analysis of Positioning Platform in LED Packaging Equipment
Authors: Xiao Yong Shan , Jiang Jun Xia , Zhao Zhen Yu
Published: February 2014

With the continuous development of LED industry, speed and accuracy requirements of LED packaging equipment is more and more high. To further improve the operation speed, it is very important to improve the stability of the positioning platform. Based on MSC.ADAMS(Automatic Dynamic Analysis of Mechanical Systems),the dynamics simulation model of the positioning platform in LED packaging equipment is established, and the effects of the assembly precision is researched on the machine performance. The method provides the theoretical basis and practical guidance for LED assembly process, and thereby can improve the operation speed and stability of the packaging equipment.
Experimental and Numerical Simulation Investigation on Dynamic Response of Liquid Storage Tanks under Seismic Excitations
Authors: Liu De Yu , Fang Zhou
Published: February 2014

A large-scale earthquake simulation experiment about the unanchored cylindrical steel liquid storage model tanks has been completed. The self-vibration characteristics of the model tanks with liquid inside were investigated based on the experimental data of the acceleration dynamic response. The seismic table test, the analysis methods are designed and conducted, and experimental results of the model tanks were carefully measured. Furthermore, ANSYS finite element software was used to simulate and calculate the low order natural frequency and fundamental frequency of the model tank systems according to the national design standard. The reasons for the existence of consistency and differences between the results obtained from experiments and numerical simulation were discussed.
An Efficient Modeling and Meshing Method for the Finite Element Calculation of the Ship Magnetic Field
Authors: Cao Jun Hong , Zhuang Biao , Mu Hai Fang , Zhang Di
Published: February 2014

Geometry modeling and meshing are directly related to the effectiveness and accuracy of the finite element calculation. In order to improve above two key technologies, small size ferromagnetic objects on the ship deck are simplified, and the parametric idea is introduced into the ship model meshing. A typical ship model is set up on the platform of software FLUX. The above improved technologies are tested in FLUX in the earth magnetic environment. The experimental results show that the simplified modeling can greatly reduce the amount of calculation, and parametric meshing can effectively improve the computational efficiency, which proves that the above improved method is an efficient method for the finite element calculation of the ship magnetic field.