bluuebunny/crossref_metadata_2025 huggingface dataset:
Application in Aerospace Experiment Field for Intelligent Power Supply and Distribution Monitoring System
Authors: Su Qiang , Xu Peng , Xiong Wei
Published: June 2012

According to applying feature of power supply and distribution system in aerospace experiment field, the intelligent monitoring system is designed by adopting hierarchical distributed network structure which includes field layer, network layer, management layer, and command center layer. The monitoring software based on configuration software realized such functions as unify electric force management, optimize electric force balance, economize electrical energy loss, extend lifetime of equipments, improve qualities of environment protection, promote efficiency and managing level. Applying result indicates: the system satisfies the requirement of aero experimenting task.
Applications of Lagrange-Quasi-Newton Method in Power System Steady-State Security Region
Authors: Li Zhong Cheng , Zhang Bu Han , Mao Cheng Xiong , Wang Kui
Published: June 2012

With the proportion of the installed capacity of wind farm in the grid increasing, the impact of wind farm on the power system security becomes obvious. The steady-state security analysis is one of the important measures to improve the power system security. Based on DC flow, considering the available transmission capability limit, the paper chooses the biggest security region volume as objective function with the upper and lower limits of security region multi-dimensional cuboid being as control variables, which transforms the maximum steady-state security region into nonlinear programming problem with linear constraints. This not only includes the biggest points for the safe operation, but also the order expansion problem doesn’t exist. Then Lagrange-Quasi-Newton is used to solve the equation, and the analysis of the example proves the feasibility of the proposed model and algorithm. Then we assume that wind speed distribution is weibull distribution, so we can assess the safe operation probability of wind power.
An Optimization Method of Heat Exchanger Network for Non-Fixed Investment Costs
Authors: Hu Xiang Bai , Cui Guo Min , Xu Hai Zhu , Wang Jin Yang
Published: June 2012

In order to overcome the difficulty of easily falling into the local minimum solution during the optimization process of heat exchanger network which is not considered fixed investment costs, an innovative method was presented. The total areas of local minimum solution were distributed equally, and then the distributed areas were assigned to initial areas for further optimization. The better local minimum solution was sought out after jumping out of local minimum solution. Through some case study, it presents that this optimization method is able to obtain better optimization results which is more suitable to industrial applications.
Improvement of Thevenin Equivalent Parameters and Computations
Authors: Wang Ming Qiang , Zou Wei Wei , Zhou Xiao Hua
Published: June 2012

In this paper, the conventional method to acquire Thevenin equivalent parameters is described. The method is based on features of power systems and utilizes the base-case system information. Considering the impact of loads on Thevenin equivalent potential and impedance, this paper makes improvements and brings it closer to the actual situation. The necessary condition about limit power transmission is derived, and the impedance modulus margin can be used to determine voltage stability of power system. Finally, the results of IEEE-14 bus system calculations show effectiveness of the method.
Application of Fluidization Reconstruction Energy-Saving Combustion Technology on 300MW CFB Boiler
Authors: Su Jian Min , Hu Nan
Published: June 2012

Aiming at high power consumption by auxiliaries of circulating fluidized bed (CFB) boiler, combustion tests were carried out on a 300MW inferior anthracite fired CFB boiler to decrease the bed material inventory via energy saving combustion technologies for CFB boiler based on fluidization reconstruction. The effects of fluidization reconstruction on boiler performance improvement were analyzed. Application practices show that after fluidization reconstruction, the power consumed by auxiliaries of the CFB boiler decreases obviously. Auxiliary power ratio of the 300MW boiler unit has been reduced from 6.1% to 4.3%. The erosion of boiler heating surface has been alleviated obviously.
Power Line Carrier-Based Networking Technology of the Internet of Things
Authors: Yin Hua , Long Bin Fa , Wang Nai Zhou
Published: June 2012

This article discussed the basic principles of the power line carrier application technology and an example scheme, The unique advantage of the power line carrier networking technology is applied in the Internet of things. The advantage of the application of the power line carrier in the difficult environment of radio frequency application and layout is pointed out.
Power Quality Enhancement Using a Novel Hybrid Active Power Filter Device Under Nonlinear Loads
Authors: Yun Wei Jun , Yao Gang , Zhou Li Dan , Chen Chen , Pan Jun Min
Published: June 2012

Nonlinear loads generate a large amount of characteristic harmonics , deteriorate the power quality of power distribution systems in Advanced manufacturing enterprises. In this paper a novel hybrid active power filter is proposed which consists of a series thyristor switched filter (TSF) and small rated shunt active power filter(APF). TSF is tuned at fifth and seventh order harmonic frequencies. Consequently APF compensates for third and other order harmonics, unbalance current and reactive power. A new control method based on PHC strategy is presented for APF. The device has already got an application in one of the transformer substations of a automobile factory. It’s revealed that the proposed device can improve the power factor , reduce the harmonics injection and enhancement power quality of the power distribution systems.
The Influence of Multiple Low Frequency Oscillations on Power Transmission Capability and Their Solutions
Authors: Wang Bin , Li Jing , Li Ying
Published: June 2012

There might be dynamic stability problems with multiple low frequency oscillation modes in power system with long distance and large capacity power stations, especially with clean energy stations, which may cause ” seesaw effect” between every power base, and restrict the power transmission capability. Considering this problem, an appropriate integrated solution is put forward according to the factors and measures for each mode. It is proved effective from the view of oscillation suppression and power transmission capability increasing by time domain simulation and frequency domain simulation.
Collocation Trefftz Method for the Heat Conduction Issue in Irregular Domain
Authors: Fan Hong Ming , Zhang Dan , Yu Hang
Published: June 2012

Rules for non-orthogonal borders of irregular domain is the thorny issues when using analytical method for solving mathematical and physical equations. On the basis of solution in the form of separated variables, the border of arbitrary shape with non-orthogonal boundary will be separated into a limited number of discrete points, and then direct assignment for the form solution at each of the discrete points on the border according to boundary conditions, at every discrete points on the border can establish an equation. If the number of discrete points on the border is the same with truncated series after retained series, all coefficients of the form solution can be determined and the problem solved. This paper use Laplace equation as an example to illustrate Collocation Trefftz Method can solve certain steady-state heat conduction problems within non-orthogonal border and irregular domain.
The Research of C-Type of Traveling Wave for Fault Location in Distribution Network
Authors: Liu Ya Nan , Yan Feng , Miao Qian , Jiang Jun , Xu Hai Mei
Published: June 2012

On the basis of analysis on difficulty of a single phase grounding fault locating in distribution network, a fault location method using C-type of traveling wave is put forward. The C-type of traveling wave location method is off-line. This location method can not be affected by the signal intensity of traveling wave when the fault is taking place and would be used repeatedly. As a result, the measure accuracy is guaranteed. Through the simulation to traveling wave’s process of reflection and refraction by ATP, the result what simulation experiment shows by putting up model of 10kV line with 3 branches single phase grounding fault, we can compare waveform of the normal phase and the fault phase to find the first waveform distortion point and determine the fault location. The fault location precision meets accuracy requirements, so it is feasible to locate the fault by using C-type of traveling wave location method.
Feasibility Analysis of Co-Firing Discard-Oil for Power Generation
Authors: Wang Ping , Zhou Hui Bo
Published: June 2012

This paper first introduced the harm of discard-oil and the state quo of its reuse development, and then put forward an idea of co-firing discard-oil for power generation and analyzed its feasibility. It was concluded that this idea is completely feasible with appropriate process design, reasonable mxing ratio and proper environmental protection measures.
Facility Monitoring Device Developing for the Insulators Leakage Current Detection
Authors: Mo Fu Jiang , Pan Ying Yu , Xu Hai Dong , He Ming Li
Published: June 2012

In the smart power grids construction and for the needs of the power distribution reliability，and for the overhaul and maintenance of the power equipment, it is important for all the operation equipment condition being under monitoring. All equipment has its own characteristics. These characteristics give the customizing messages for monitoring the equipment condition. For the overhead lines insulators, its leakage current mainly mirror insulating property and can give out the insulating strength degrading in time. So trying to monitor the insulators leakage current is significant for Electrical safety. In this paper, the polluted insulator leakage current generating mechanism and characteristics in the operating voltage be analyzed, the actual use of the leakage current on-line monitoring methods and equipment be compared. Based on MSP430 single chip, one facility insulator leakage current online monitoring device is developed. This on-line monitoring device make up of leakage current signal acquisition unit, periodically the leakage current signal into the signal processing unit, the microcontroller to process data effectively, and given the alarm in case of problems, and the data stored by the host computer communication module and communication. By preliminary testing on the good and polluted insulator, the test data reflect the polluted insulator leakage current changed condition, and can find out fault insulators nicely.
Function and Dynamic Performance Test of the Updated Tian-Guang HVDC Control and Protection System
Authors: Ou Kai Jian , Li Hai Ying
Published: June 2012

After ten years operation, Tian-Guang HVDC control and protection system will be updated. The Tian-Guang HVDC physical simulation system and RTDS simulation system were set up in this paper. Based on these two simulation systems, the function and dynamic performance of the updated Tian-Guang HVDC C&P system were tested. Totally 30 test groups and more than 300 test items are included in the testing matrix. And the simulation results in the physical simulation system were compared with those in the RTDS simulation system. The C&P software were optimized and improved during the test. The test shows that, the control and protection strategies and parameters used in the upgraded HVDC system perform well and meet the criterion.
The Electrical Insulation Property of PTFE Cannula in High Elevation
Authors: Zhang Xu , Li Chuan , Li Yu Hui , Yang Hong Wei , Li Jian Fa
Published: June 2012

The polytetrafluoroethylene (PTFE) with the good dielectric property is a kind of nonpolar material. Made from the PTFE, the cannula has the high electrical insulation performance. This cannula can be applied to the equipment which requires for the high electrical insulation. There are 3 kinds of power-frequency voltage resistant experiments on PTFE cannulas with the inner diameter and outer diameter of 0.55/1.35, 0.7/1.5, 0.96/1.6, 0.46/0.96, 1.5/3.0 in the 1970m elevation. The PTFE cannulas are tested at the 85kV power-frequency voltage with the pure condition, the humidity condition, and the polluted condition separately in 1 minute. The result induced that the PTFE cannula did not be destroyed in all of the above experiments with no puncture sound, no smoke, no flashover and no burning. The insulating quality of the PTFE cannula is satisfied with the insulation requirement of the 85kV, i.e., the pollution level I.
The Research of the Status Quo and Development of UHV Transmission Lines Construction in China
Authors: Liu Ji Wu , Xiong Yan Hong , Ji Yang
Published: June 2012

The construction of UHV (ultra-high voltage) transmission lines has become an important part of the planning of “smart grid" and “solid grid” in China. This article elaborated in recent years the UHV transmission lines construction status and possible problems, has made a comparative analysis on the angle of environmental carrying capacity, and put forward three effective suggestions, in order to improve the construction efficiency of UHV transmission lines engineering.
Application of Fuzzy PI Control to Speed Control System of Brushless DC Motor
Authors: Hu Fa Huan , Qiu Xiao Tong , Tang Jun
Published: June 2012

Basing on analysis the principle and mathematical model of the brushless DC motor, the paper proposes a control model on the basis of speed loop and current loop, fuzzy PI control model is adopted in the speed loop, and traditional PID control model is used in the current loop. It is showed that when the load or parameters vary, comparing to traditional PID control model, the fuzzy PI control model gets less fluctuation and better robustness.
Calculation and Analysis of Winding Temperature Rise for ODAF Power Transformer
Authors: Li Yan , Jing Yong Teng , Li Longnv
Published: June 2012

The AutoCAD, Gambit and ANSYS software are used to establish transformer oil flow-temperature rise model and mesh generation based on finite volume method, fluid mechanics and numerical heat transfer. A method that calculates temperature rise distribution of transformer winding regional wire and oil by FLUENT software, and a numerical example is given for an actual transformer.
Study on Low-Speed High-Torque PMSM for Surface-Drive System of Progressive Cavity Pump
Authors: Zhang Bing Yi , Wang Shuai , Feng Gui Hong , Cheng Xiang
Published: June 2012

This paper focus on a surface-mounted low-speed high-torque permanent magnet synchronous motor (PMSM) for progressive cavity pump wells. To minimize torque ripple, several methods is used such as proper pole-arc coefficient and fractional-slot windings. In the motor design, a non-linear finite element analysis (FEA) method is conducted to compute the performance of the motor. Through the simulation and experiment, the result shows that the design of low-speed high-torque PMSM is valid and presents a good performance.
The Effect of Misfire on the Emission and Engine Performance of a Single Cylinder Motorcycle Engine
Authors: Wu Chang Tai , Lu Liang Chun , Lu Jau Huai
Published: June 2012

A misfire controller developed by the authors was used in this paper to investigate the effect of misfire on the emission and engine performance of a single cylinder motorcycle engine. Three kinds of test were carried out, the idle test, the engine dynamometer tests, and the chassis test. It was found that in the engine dynamometer tests, the concentration of unburned hydrocarbons in the engine exhaust was raised and the engine torque declined as the misfire rate increased. The variations of the CO and CO2 are not the same in different operating conditions. At low load, CO concentration increased with the misfire rate while CO2 moved in an opposite direction. Contrary condition happened at high load. The CO2 concentration increased with the misfire rate while CO varied in the opposite way. Results of idle test showed that misfire would cause moderate deterioration of engine emission. However, chassis dynamometer test showed that even 1% of misfire would cause severe increase of emission.
The Electromagnetic and Thermal Analysis of Permanent Magnet Brushless DC Motor in Cars
Authors: Li Yan , Qin Ying , Liu Yong Zhi , Xia Jia Kuan
Published: June 2012

As the wide application of DC brushless motor in cars, this paper introduces a kind of motor design method that based on finite element theory. The motor electromagnetic simulation is analyzed by using finite element termed as Ansoft, the simulation results and experimental data are anastomotic, so the method is verified feasible. The motor in cars is restricted to the volume, the motor temperature index influence all basic parameters seriously, in this paper baseing on the motor loss simulate the motor 3D temperature distribution, and find out the highest spot, for designing the cooling system of similar motors provide instructional effect, and this is of important engineering significance.
Design of Intelligent Power Meter for Demand Response of Smart Grid
Authors: Chen Chao Shun , Ku Te Tien , Lin Chia Hung
Published: June 2012

To support the demand response function for smart grid, an intelligent power meter with hybrid communication module has been proposed in this paper. The circuit module consisting of VI measurement, power calculation chip, microprocessor and PLC/ZigBee/RS-485 communication is designed to support load control to achieve load reduction after receiving the demand response command of via two way communication. The load control function can also be activated by the real time pricing information, which has been downloaded from utility control center. The embedded power management system is developed to perform the management of intelligent power meters to monitor and control electrical appliances. Based on the field test, the intelligent power meter can be used for load shedding or power due to achieve energy conservation and enhance system stability for smart grid application.
Design of Ultrasound Acquisition System Based on FPGA
Authors: Yan Ming Jun , Yan Shao Feng
Published: June 2012

FPGA has the user programmable ability, like the software, it can be programmed. In this paper, we designed ultasonic detection circuit, and gives the hardware and software design. The Signal Tap II the logical analyzer show that, the system can acquisition at high speed, and can work in real-time
High Impedance Fault Identification Method of Distribution Networks
Authors: Huang Yong , Chen Min You , Zhai Jin Qian , Yan Hong
Published: June 2012

Abstract. High impedance fault has always been difficult for distribution network fault identification due to its unobvious fault signature and difficult detection. This paper decomposed the transient signal in multi-scale by utilizing the good localization performance of the wavelet in both time domain and frequency domain, reconstructed the wavelet coefficients under each scale, took the wavelet reconstruction coefficient which was under the scale 3, calculated the size spectrum of each feeder line in timing floating window and identified the circuits in which the faults lined according to the value of the size spectrum. The high impedance fault simulation system was built based upon the study of the various transient signals in power systems, and the high impedance fault simulation analysis of the distribution feeder was undertaken through PSCAD simulation platform using high impedance fault model. Simulation analysis showed that the method could effectively extract the feature of high impedance fault on high impedance fault identification.
Power Management of a Stand-Alone Hybrid Wind/PV Integrated Oxygen Generator and Water Treatment Equipment System
Authors: Mei Jiang Ping , Cheng Xing Quan , Liu Yi
Published: June 2012

The hybrid wind/PV(photovoltaic) system supplies more stable power than a single wind or PV source so that the combined utilization of the wind turbine and PV array is becoming increasingly attractive. “The stand-alone hybrid wind/PV integrated oxygen generator and water treatment equipment system” is a new application of the hybrid wind/PV system. This paper deals with the power management strategy of the system for satisfying the demands with the limited coming energy. For the reason that the system is a completely new use, the system configuration is put forward in the first place. As a basis, this paper then analyses the main components’ characteristics. At last, on account of the system configuration and the main components’ characteristics, the power management strategy of the system is proposed.
Research on Conducted EMI in Power Converter
Authors: Liang Bin
Published: June 2012

This paper researches differential mode (DM) conducted electromagnetic interference (EMI) in rectifier. The DM interference source generated by power electronic switches is given. Based on experimental and theoretical analysis, the conducted EMI of a three-phase rectifier is studied systematically. The study shows that it changes with resistance loads in low frequency ranges, while in high frequency bandwidth, the effect of change of the resistance load on the DM EMI is not obvious. The validity of the models is confirmed by the measurements.
Sample Time Staggered One-Cycle Control Based on Three-Phase H-Bridge Cascade VSI
Authors: Fu Lan Fang , Sun He Xu , Zhu Yan Cai
Published: June 2012

The One-Cycle Control(OCC) technique not only provides fast dynamic response, but also can admirably suppress the perturbation yielded by dc source and eliminate the undesired harmonic contents.The cascade H-bridge VSI has very low dv/dt and distortion in the voltage output waveform.Sample time staggered one-cycle control（STS-OCC） based on three-phase H-bridge cascade VSI is proposed. It yields all of the advantages of the OCC and cascade VSI.The results of the simulation and analysis show that the STS-OCC technology has high equivalent work frequency, little switching loss and quick dynamic response speed, which means it is fit for the cascaded multilevel inverter.
The Three-Dimensional Design for Device of Feeding Paper on the Small Offset Press Based on Pro/E
Authors: Xu Shun , Zhang Yan
Published: June 2012

This article does three-dimensional design for feeding device of octavo and color small offset press based on the pro/E software. It analyses the role of each part separately, requirements, and the working principle. And it does the design for the main transmission mechanism. The three-dimensional design of the device provides reference and basis for production and manufacturing of the printing press.
Experimental Study of Treating Discarded Circuit Boards by Using the Converging - Extended Anode Channel Plasma Torch
Authors: Wang Song Bai , Cheng Chang Ming , Lan Wei , Zhang Xian Hui , Liu Dong Pin , Yang Si Ze
Published: June 2012

In this paper, some discarded circuit boards in the plasma incinerator were incinerated by the converging - extended anode channel plasma torch, whose work principle and composition was described, and two experimental results were described, finally, the percentage of four major exhaust gas (CO, NO, SO2, O2) was reported, showing a good prospect on treating electronic waste with using the plasma torch.
Research on Disassembly Sequence Planning in DFD
Authors: Yu Yuan Zheng
Published: June 2012

The problems of automatic disassembly direction computation and disassembly sequencing must be solved in DFD. The computation rules have been set based on freedom intersection. Applying constraints elimination and assembly construction mapping, sequence generation has been realized by heuristic algorithm. To simplify the planning procedure, a modulized construction model has been developed for top-down computation. The principle could be applied for CAD software development in DFD.
The Determination of Electrokinetic Coupling-Coefficient and Zeta Potential of Rock Samples by Electrokinetic Measurements
Authors: Wang Jun , Hu Heng Shan
Published: June 2012

The electrokinetic effects are important in the understanding of electric properties in porous medium. In this study, the streaming potential and streaming current of saturated samples are measured at different concentrations, then three methods are applied to obtain the zeta-potential and electrokinetic coupling coefficient. The study shows that the results obtained from streaming potential and streaming current methods agree well with each other, but the results obtained from simplified streaming potential method become seriously inaccurate at low concentrations due to the influence of surface conductance. This experimental study also provides a reliable estimate of the surface conductivity and its contribution to zeta-potential at given concentrations.
A Power Tracking Control Method for Single-Phase PWM Rectifier
Authors: Yan Shi Jie , Gao Wen Zhong , Chu En Hui
Published: June 2012

Power control method had been widely used because of its simplicity, good dynamic performance, decoupled active and reactive power control for three-phase PWM rectifier. But it is not adapted to single-phase rectifier as power calculating problem. A power tracking control method is proposed for single-phase PWM rectifier. In new method, voltage and current with harmonics are decomposed of Fourier series. Their fundamental components are only extracted in order to calculate active power and reactive power and track requirement value. So the system not only realizes high power factor, sinusoidal current and stable DC link voltage, but also meet the application demand the capability of power regeneration to the power supply. The results of experiment show that the DC link voltage fluctuations should be minimal and the power factor is high. The proposed method is effective and practicable.
Analysis and Design of a Dual-Mode Control Boost Rectifier
Authors: Lo Yu Kang , Lin Jing Yuan , Wang Chao Fu
Published: June 2012

This paper presents a dual-mode control scheme for a boost rectifier at both extreme loads. The transition-mode (TM) technique is adopted to reduce the switching loss at light loads. On the other hand, the fixed-off-time (FOT) control with continuous conduction mode (CCM) operation decreases the conduction losses at heavy loads. The principles and design procedures of the proposed dual-mode controller are discussed and analyzed. Finally, a 300-W dual-mode boost rectifier with an output voltage of 380 V is implemented with satisfactory experimental results.
Radiation Effect of MOS Structure Irradiated by 0.8MeV Electron Beam
Authors: Zhang Jian Xin , Liu Jun Xing , Wan You Bao , Sun Ying Hui
Published: June 2012

Metal-oxide-semiconductor (MOS) structure is highly sensitive to SiO2-Si interface. It will reflect parameters such as interface density and oxide layer charge expediently. For the sake of researching of radiation effect of MOS structure irradiated by electron, we adopted 0.8 MeV electron at dosage between 2×1013cm-2~1×1014cm-2as radiation source respectively. We found that electron radiation will induce interface density at SiO2-Si interface. According to comparison with C-V curve of MOS structure at high frequency and low frequency, we obtain that the experimental data of interface density is up to 1014(cm-2eV-1). In addition, we also obtain the relationship between the parameter and radiation dosage.
Electrical Characteristics of Stacked Titanium Oxide/Aluminum Oxide by Atomic Layer Deposition on (NH4)2 S-Treated Gaas
Authors: Lee Ming Kwei , Yen Chih Feng , Yang Sheng Hsiung , Lee Jung Chan , Cheng Chi Hsuan , Cheng Wei Hau
Published: June 2012

The (NH4)2 S treatment was used for the reduction of native oxides and passivation on GaAs. Atomic layer deposited Al2O3 can further remove the residue native oxides and lower the leakage current on (NH4)2S treated GaAs from self-cleaning and high bandgap. For further stacked with high dielectric constant TiO2 also prepared by atomic layer deposition on Al2O3/(NH4)2S treated p-type GaAs MOS capacitor, the leakage currents can reach 1.9 × 10-8 and 3.1 × 10-6 A/cm2 at ± 2 MV/cm. The dielectric constant is 25.
Stability in the Special Saturated Liquid Film along an Inclined Heated Plate
Authors: Fan Xiao Chao , Shi Rui Jing , Wei Bo
Published: June 2012

Stable analysis of flow and heat transfer in the saturated liquid film of liquid low boiling point gases falling down an inclined heated plate is investigated. Firstly, the boundary value problem of linear stability differential equation (Orr–Sommerfeld equation) on small perturbation is derived representing surface tension by nonlinear relationship on temperature. Then, the expression of the wave velocity is got by solving the boundary value problem of O–S equation using the perturbation method. The effects of the inclined angle and some other factors, such as Reynolds number, wave number, temperature of the plate and the parameter for the physical property, on stability in the saturated liquid film of liquid low boiling point gas N2 are numerically analyzed by MATLAB software. Finally, it is shown and analyzed a new critical Reynolds number which is actually the extension of Yih’s.
Study on Thermal Volatilization of Soybean Biodiesel and Its Blends
Authors: Lai Yong Bin , Chen Xiu , Ge Wu Jie , Lu Cui Ying
Published: June 2012

Thermal analysis has been employed to yield information on the volatility of the biodiesel/petrodiesel since the volatility influences the ignition quality of the fuels in a compression ignition engine. The chemical composition of -10 petrodiesel (-10PD) and soybean biodiesel (SME) was analyzed by gas chromatography-mass spectrometry. The thermal volatilization of biodiesel and its blends was investigated by thermogravimetry and liquid volatile theory. Volatile index was put forward for describing biodiesel/petrodisel volatility. A good correlation model was proposed for calculate the biodiesel/petrodiesel volatility by biodiesel blending ratio. The study showed that -10PD was mainly composed of long chain alkanes: C8–C26. SME was mainly composed of long chain fatty acid methyl esters: C14:0–C24:0, C16:1–C22:1, C18:2 and C18:3. The volatile indexes of SME and -10PD were, respectively, 1.74E-04 and 3.64E-05. The biodiesel fuel was considerably more volatile in comparison to the petrodiesel fuels. The SME/-10PD volatility had relation to SEM blending ratio, it was better with increasing the SME blending ratio.
A Research on Superheated Steam Temperature Control Optimization of the Thermal Power Plant on the Basis of Steam Temperature Characteristics
Authors: Yao Jia Fei , Wang Li Yang
Published: June 2012

Take the superheated steam system of a 330MW unit as the object, by means of the collection and research on the data of the overheating system of thermal power units and simulation tools in matlab, the results were analyzed, and then presents a construction method of the dynamic compensating function which take the load as the variable, at last, simulate and verify the constructor function.
Experiment and Analysis on Temperature Distribution of Peanut Shell Molding Fuel Hot-Blast Stove Furnace Chamber
Authors: Guo Qian Hui , Chen Min , Liu Sheng Yong
Published: June 2012

Under four different working conditions (the smallest air door αpy =1.20,the smaller air door αpy =1.60, the larger air door αpy=2.30 and the largest air door αpy=3.50), the Peanut shell molding fuel Hot-blast Stove designed by the author have been tested. The corresponding result showed that the temperature distribution had similar rules in height, depth and width. The more reasonable and economical operations of the Peanut shell molding fuel Hot-blast Stove have been realized under the working condition 2 and 3. Their combustion efficiency of the boiler can reach 84.95％-92.07％and the thermal efficiency can reach 46.68％-56.73％. They have provided an effective way to solve the problem of heating in rural areas.
Feasibility Study on Accessorial Limestone Injection Desulfurization System on Large Capacity Boiler
Authors: Wen Zhi Yong , Zhang Cheng , Fang Qing Yan , Chen Gang
Published: June 2012

Many large capacity boilers are facing the problems of desulfurization with the variation of coal quality received and small designed desulfurization capacity in current Wet Flue Gas Desulfurization(WFGD) system. WFGD capacity improving renovation is a high cost and long construction cycle project. Therefore, a proposal to add accessorial limestone injection desulfurization system without changing the current WFGD was investigated in this study. Laboratory experiments and pilot scale field tests on a 220t/h boiler were performed to certificate the possibility of adding accessorial limestone desulfurization system on large capacity boiler. Desulfurization efficiencies under different injection position, Ca/S ratio, the porosity structures of desulfurization agent, and boiler operating conditions were tested to obtain the optimal working conditions for limestone desulfurization in large capacity boiler ; Ash composition, ash melting point, ash particle size distribution were also determined to evaluate the influence on heating surface of boiler corrosion, fouling, abrasion and boiler efficiency on a 660MW unit boiler after adding limestone injection system for security and economy concern. The results of this paper could provide reliable evidence and experiments data for the power plant to make overall consideration for adding accessorial limestone injection desulfurization system without changing the current WFGD system.
Numerical Implementation of a Thermomechanical Constitutive Model for Shape Memory Alloys Using Return Mapping Algorithm and Microplane Theory
Authors: Mehrabi Reza , Kadkhodaei Mahmoud , Ghaei Abbas
Published: June 2012

In this work, a return mapping algorithm is utilized to implement the model into a finite element program and then Microplane theory is employed. A numerical procedure is also developed to implement the model as a user material subroutine for ABAQUS-Standard commercial code. Uniaxial tension test under a constant axial stress is simulated in order to study the behavior of shape memory alloys. A very good agreement is seen between the results obtained by the two approaches indicating the capability of microplane theory.
Numerical Simulation on Thawing Time of Frozen Coal in Tram
Authors: Chen Chao , Ouyang De Gang , Song Zhong Hua , Li Ming Hui
Published: June 2012

In this paper, numerical simulation on thawing of frozen coal in tram of coke-oven plant was carried out. Simplified physical and mathematical models were developed and calculated, based on which the rules of coal thawing were obtained. By analyzing effects of wind temperature and wind speed on thawing, thawing time of frozen coal under different conditions was calculated, which can provide reference for accurate design and actual operating.
Research on Flame Combustion Stability Based on Neural Network
Authors: Bai Gui Zhi , Zhang Li Hong , Chen Shu Qian
Published: June 2012

For the use of boiler flame image analysis to detect the boiler flame combustion stability, when the combustion affected by coal, peaking , improper operation or other effects, the flame appeared short pulsation. In general, the traditional detection methods based on gray scale variance can not avoid the impact of flame pulsation on account of the inaccuracy of the boiler combustion stability detection. This paper presents a flame combustion instability detection method based on neural network and selects multiple features which are directly related to the flame stability as neural network input vector. Experiments show that this method can fight off the tiny ripple influence caused by the impurities combustion or peak and simultaneously, greatly improve the detection accuracy and stability.
Research on Trait in Heat Exchange and Flow of Inner Single-Phase Currentin Micro Channel
Authors: Hu Yue Lian
Published: June 2012

During recent years,micro-channel heat transfer technique has been successfully used in many practical situations，and has notable advantages of high heat transfer efficiency and compact configuration.It is an important subject in modern hydrodynamic and heat transfer research field.Computational fluid dynamic program CFX will be used in this article to simulate flow and heat transfer of single-phase water in micro-channel ,flow and temperature felid will be described visually in CFX, and this object is searching a new method to research more flow and heat transfer of single-phase water.
Numerical Simulation of Infrared Signature Emitted by Liquid Rocket Plume Using Wide Band K-Distribution Model
Authors: Yin Xue Mei , Liu Lin Hua , Li Bing Xi
Published: June 2012

A new wide band k-distribution model has been developed and used to investigate infrared radiation signatures of liquid rocket plume in some detectors’ working spectrum regions, in which the temperature and the gas molar concentration fields are solved using engineering empirical formulations. Based on the line parameters in HITEMP database, absorption coefficient variables of water vapor and carbon dioxide corresponding to 12-point Gauss-Lobatto quadrature points are derived and expressed as a simple formulation. The absorption coefficient variables of mixture are obtained by summing the absorption coefficient variables of individual gas species under the hypothesis that the k-distributions are statistically uncorrelated. Its validity for the numerical prediction of liquid rocket plume radiation is verified by comparison with line-by-line approach (LBL). Compared with line-by-line calculations, the maximum relative errors of the new band model are less than 10 % in the detectors’ working spectrum regions, while the computational time of the new band model is less than 1/1000 of LBL. The effects of fly parameter on infrared radiation signatures of liquid rocket plume are studied using the new model. The results showed that the integral radiation intensities of liquid rocket plume increase with the nozzle exit temperature, Mach number and the ratio of nozzle exit pressure to atmospheric pressure. The radiation intensity variation trend for liquid rocket plume with altitude is different for different detectors’ working spectrum regions.
Research on Welding Repair for Reheating Hot Pipe Elbow of 325MW Station Boiler
Authors: Zheng Xiang Feng , Wang Qing , Feng Yan Ting , Niu Xiao Guang , Hao Xiao Jun , Li Wen Bin , Xu Xue Xia , Sun Peng
Published: June 2012

Through methods, such as microscope analysis, metallographic examination, the crack located nearby the fusion line between reheating hot pipe elbow and blocking valve is reheat crack. The base metal material and excessive welding residual stress are the primary inducement of crack. In replacing pipe elbow, the measures of reducing residual stress, such as hammer blowing ,lower welding heat input, post welding heat treatment and so on, were taken. The welding repair succeeded greatly.
The Coupled Simulation Research on Engine Cooling System
Authors: Cai De Hong , Ren Cheng Qin , Liu Jing Ping
Published: June 2012

Abstract: With the help of field experiments, a 1-D/3-D coupled simulation model between automo-tive engine cooling systems and engine cabin is established. Through these experiments and coupled simulations, the influence of engine cabin on the performance of engine cooling system and thermal flow field has been analyzed, and convective heat transfer coefficients on the engine surface which contacted with engine cabin’s thermal flow field have been summarized. These heat transfer coeffi-cients provide basic arguments for developing engine cooling system efficiently.
The Parameter Variation in Pressure Vessel during Loading Operation by Considering Heat Transfer Impact Based on Real Gas Model
Authors: Wang Wei Qing , Yang Li , Lv Shi Gui
Published: June 2012

Since the molecular force and the molecular volume were ignored in the ideal gas model, and it was less accurate when the ideal gas model was used to depict characteristics of real gas under high pressure, so the real gas model was adopted and the heat transfer was considered, the dynamic variation model was set up for internal gas in the pressure vessel during loading operation. The model was solved by using the numerical simulation method of Runge-Kutta. Comparison was made between the ideal gas model and the real gas model under adiabatic and non-adiabatic conditions, it showed that under low pressure the results obtained by the two models were in good agreement, but under high pressure the deviation was enlarged, the real gas model with considering the heat transfer influenced would be more coincident with the reality.
Theoretical and Experimental Investigation of Micro Feeding Technology on a Drop Tube Furnace
Authors: Ma Zheng Zhong , Xu Xiang , Xiao Yun Han
Published: June 2012

Coal particles are supplied to drop tube furnace (DTF) with a designed shaftless screw micro feeder. The condition of individual particles in furnace, which demands small particles size (102μm) and low flow rate for micro feeder，is desired to reaction mechanisms research. When particle size is less than 1mm, the interparticle forces such as van der Waals interactions have enormous effect on flow behavior of particles, so it is difficult to provide continuous and steady particles flow at low flow rate. In this paper, the micro feeder uses shaftless spring as its feeding element. To simulate dispersed particles flow, the feeding rate of coal particles should be decided by feeding coefficient M and is controlled by variable rotation speed of screw. The corresponding simplified model of feeding rate is presented, and interparticle forces are evaluated by the velocity coefficient . A vibrating metal rod is inserted into the middle of the shaftless screw to avoid particles agglomeration, and particle flow stability is also effectively improved. The given results show good linearity and stability of micro feeder. Moreover, the influences of the particle properties such as particle size and particle moisture content on the feeding rate are also investigated.
Thermal Analysis of a Dynamic Lithium-Ion Battery during Charge
Authors: E Jia Qiang , Long Yan Ping , Hu Xiao Feng , Zhu Rong Jia
Published: June 2012

Four types of heat sources of a dynamic lithium-ion battery (LIB) during charge were studied, and temperature distributions inside the dynamic LIB caused by the four kinds of heat generation sources with different currents and temperatures during charge were simulated by using a electrochemical-thermal three-dimensional model. The ohmic heat is the largest heat resource with about 63.5% in the total heat generation during regular charge, the electrochemical reaction heat is dominant when the SOC is below around 10%, and the subsidiary reaction heat can not be ignored when the temperature in the battery is above 80°C. Current as well as ambient temperature plays a very important role in the overall thermal behaviors of the battery.
Thermal Decomposition Characteristics of Calcium Based Organic Compounds under Carbon Dioxide Enriched Atmosphere through Thermogravimetric Analysis
Authors: Niu Sheng Li , Li Ying Jie , Han Kui Hua , Zhao Jian Li , Lu Chun Mei
Published: June 2012

Thermal decomposition characteristics of two kinds of calcium based organic compounds-calcium propionate and the product of the modified calcium hydroxide by propionic acid-under O2/N2 atmosphere and O2/CO2 atmosphere are investigated through thermogravimetric analysis. Thermal events of CP and MCP are divided into three segments. The second and the third ones for the two compounds are similar. O2/CO2 atmosphere reduces mass loss rate peak of the second segment and postpone the third segment. O2 concentration of 10 % is inadequate for a fast and sufficient reaction. When O2 concentration is enriched to 20 %, the whole process is shifted towards lower temperature zone. Further heightening O2 concentration to 30 % or 40 %, the effect is not remarkable.
Basic Research of the Intercooled Turbofan Aero-Engine
Authors: Zhang Jin Chuan , Wang Yun , Zhang Can
Published: June 2012

In conventional turbofan aero-engine designs, the effective way of improvement of engine efficiency is through the increasing of overall pressure ratio and improving of combustor inlet gas temperature, but the further incresement of compressor overall pressor ratio is constricted by high pressure compressor outlet allowed temperature. The improvement of combustor outlet temperature is limited by turbine allowed inlet temperature during take-off and climbing. An intercooled core can be designed with a significantly higher overall pressure ratio also with reduced cooling air requirements, providing a higher thermal efficiency compared with a conventional core. Through the basic analysis of performance of intercooler aeroengines. It indicated that the intercooled aero-engines can decrese the feul consume clearly and have a further potential in future civil aircraft application.
A Heuristic Search Algorithm for a Dynamic Production Model with Random Factors
Authors: Zhou Yun Song , Zhang Zhi Gang , Wang Cong
Published: June 2012

Economic lot and scheduling problem is one of the focuses in the international engineering field. Aiming at several kinds of products and sets of production lines, this paper introduces a production model, which is based on the principles of artificial intelligence and introduces random factors as time changes, such as market demand and production line equipment. Besides, this paper puts forward a dynamic heuristic search production schedule method, and the simulation results show that the effectiveness and predictability of this method.
Combining Diagnosis Methods for the Fouling on Flow Path of Steam Turbine
Authors: Yang Tao , Xu Jian Qun , Li Ling , Zhou Ke Yi , Shi Yong Feng
Published: June 2012

The fouling on flow path of steam turbine would lead to the changes of thermal parameters and significantly deteriorated efficiency. In this paper, a qualitative analysis of fouling on flow path based on measured parameters was described for the preliminary diagnosis, and the zooming thermoeconomic diagnosis model combined with the equivalent flow area diagnosis model was proposed to diagnose the specific location of fault. Then the flow performance of a 630 MW supercritical unit was analyzed, and the possible fouling stages were also discussed according to the thermoeconomic diagnosis and quantitative analysis. The result of diagnosis was consistent with the situation of uncovering cylinder, which indicated that though the actual system was complex, the coupling multiple faults of flow path could be diagnosed by combining the above diagnosis models.
Experimental Study on CH4 / Air Diffusion Combustion on the Upper Surface of Porous Media Packed Beds
Authors: Huang Xin Zhang , Zhang Xiu Li , Shi Jun Rui , Xue Zhi Jia , Xu You Ning , Wang Shu Qun
Published: June 2012

This paper experimentally study on CH4/ air co-flow diffusion combustion on the upper surface of porous media packed beds. The flame height and flame shape were reconstructed from the upper and the side of the combustor. The influence of the height of the packed bed on the flame height and flame shape is reported. It is shown that the flame height decreases rapidly and the circular diameter increases rapidly with increase the height of the packed beds.