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ISSN 1674-2850
CN 11-9150/N5
 
Current Issue
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September 30,2013
Volume 6,Issue 18
Pages -
Subject Area:Geographic Information System,Energy-saving Technology,Energy Calculation and Measurement
 
Title: Study on the influence factors of the strength of carbon composite iron ore hot briquette
Authors: LI Jun, JI Qiang, LI Peng
PP: 1797-1801
Abstract: This paper focuses on the impact of moisture content, particle size and heating time of raw material on the strength of the carbon composite iron ore hot briquette, and explores the mechanism of pellet strength. The experimental results show that moisture content of raw material has little influence on the pellet strength. Coal and ore particle sizes have a great influence on the pellet strength. When the coal size is 0.180 mm and the mine size is 0.450 mm, the pellet strength is 270 kg/piece. Heating time has a great influence on the pellet strength, within this experimental condition, the best heating time is 30 min.
Keywords: powder metallurgy; carbon composite iron ore hot briquette; moisture content; particle size; heating time; strength
 
Title: Industrial test of TiB2/C composite wettable cathode material with good resistance to penetration for aluminum electrolysis
Authors: LV Xiaojun, LI Jie
PP: 1789-1796
Abstract: The experimental studies for industrial application of TiB2/C composite cathode in four 100 kA aluminum electrolysis cells were developed. Industrial test results show that compared with the cells using common carbon cathodes, the test cells have uniform current distribution, and can effectively reduce the sodium permeation rate. The average bottom voltage drop of test cells decreases by about 40 mV, and the average current efficiency increases from 92.6% to 93.9%. Power energy of 498-657 kW穐/t-Al is saved, and TiB2/C composite cathode has good wear resistance and long life.
Keywords: non-ferrous metallurgy; aluminum electrolysis; TiB2/C composite cathode; cell voltage; current efficiency
 
Title: Study of improved K-Means algorithm based on equal region division
Authors: XIAO Jianling, CHEN Guoliang
PP: 1784-1788
Abstract: In this paper, according to the prospective of increasing clustering quality, referring the thought of region division, and combining the traditional K-Means algorithms, the improved K-Means algorithms based on equal region division was put forward. The improved K-Means not only guaranteed clustering quality, but increased clustering efficiency significantly as well. The clustering results obtained were very stable. The study showed that the improved algorithm could enhance the performance of traditional K-Means algorithms, and the improved results were satisfactory.
Keywords: photogrammetry and remote sensing technology; K-Means; division; algorithm
 
Title: Design and implementation of multidimensional poverty measurement module
Authors: GUO Hui, WANG Yanhui, QIAN Leyi
PP: 1779-1783
Abstract: Based on systematic design of multidimensional poverty identifying indices system, combining the multidimensional poverty measurement model algorithm, this paper takes the key county for poverty alleviation in contiguous special poverty-stricken area—Qianjiang district in Chongqing as study area to describe the design ideas and key points of multidimensional poverty measurement module in detail. This module combines geographic information system (GIS) visualization to display multidimensional poverty level in the area as well as the poor contribution for the corresponding dimension and index in the form of pie chart.
Keywords: geographic information system; poverty identifying indices system; multidimensional poverty measurement model; poor contribution
 
Title: Establishment of mine water supply network model based on the gravity similarity
Authors: WANG Pei, JIANG Zhong’an, SHI Leilei, CHEN Jushi
PP: 1773-1778
Abstract: In order to research the reliability of mine dustproof water supply network, this paper deduces the similarity number of flow rate and pressure under the condition of abnormal similarity, and establishes the physical model of mine water supply network according to the gravity similarity criterion for the first time in Linnan mine as the background. The running status of the whole network is monitored, the flow rate and pressure of the monitoring stations are measured, and then the experiment result and EPANETH simulation result are contrasted with the data of the original network. The results show that the physical model meets gravity similarity criterion under the condition of abnormal similarity, which provides the experimental basis for the follow-up research on mine water supply network.
Keywords: mine safety; mine; water supply network; gravity similarity; abnormal similarity; EPANETH
 
Title: Characteristics of strata behaviors and support technology for gateways under deep mine in Huainan area
Authors: CHEN Denghong, HUA Xinzhu
PP: 1766-1772
Abstract: Data compilation and analysis was carried out based on relevant literatures survey of surrounding rock stability on tunnel, in-situ measure of rock stress in deep mine and testing on mechanical parameters of roadway surrounding rock, and it showed that deep roadway of Huainan area belongs to high stressed soft rocks under typical tectonic stress. The deformation of tunnel manifested to be serious floor heave, “W” type cracked on the roof and net phenomena appearred on sides of tunnel. Universal distinct element code (UDEC) numerical simulation was adopted to analyze the failure section and its reason. Support ideas were proposed according to the failure characteristics and were put into engineering practice. The result showed that deformations of surrounding rock were effectively controlled and could meet security and high efficient production need, and good results had been acquired.
Keywords: mining engineering; Huainan mining area; deep mine gateways; pressure characteristics
 
Title: Cusp catastrophic model of water-inrush from top of karst collapse column
Authors: LI Zhenhua, ZHAI Changzhi, XIE Hui
PP: 1761-1765
Abstract: A mechanical model of collapse column top is established, based on which, the expression of total potential energy function is derived. Then the cusp catastrophic model for the water-inrush of collapse column is set up by catastrophe theory. The formula of necessary and sufficient condition for the water-inrush of collapse column is obtained according to the cusp catastrophic model. In the mean time, the mechanism of water-inrush from top of collapse column is analyzed according to the model. The cusp catastrophic model indicates that the main factors of affecting the water-inrush include the size of collapse column, the nature of top strata, the depth of collapse column, the pressure of confined water, the mine pressure and so on. The establishment of model is of great significance to judge and prevent the water-inrush of collapse column.
Keywords: mining engineering; cusp catastrophic model; catastrophe theory; collapse column; water-inrush
 
Title: Study on top coal cavability of fully mechanized sublevel caving for extra thick coalseam in the condition of shallow burial depth and hard coal and hard roof
Authors: WU Jinan, XU Jinhai
PP: 1754-1760
Abstract: Based on the mine area characteristics and geological conditions, parameters of fully mechanized caving face, equipment matching and recovery process are confirmed. Periodical weighting of base roof presents characteristic of local weighting and migration rather than simultaneous weighting in the working face direction and the dynamic load factor of periodical weighting is 1.31. According to measured results of top-coal collapse lumpiness distribution, most top-coal can successfully cave down and the caving property of top-coal is good. In addition, measurement analysis has been taken to the migration rule of top-coal and roof and the distribution law of mining abutment pressure. Depending on Chinese-made equipment, the working face produces 9.887 4 Mt raw coal in 2006 and coal mining team produces 1.068 7 Mt raw coal every month. As great economic benefit has been made, and this technology is worth popularization.
Keywords: mining engineering; shallow burial depth; hard coal and hard roof; extra thick; mine pressure regularity; fully mechanized sublevel caving
 
Title: Exploration on the seismic wave propagation in confining rock near circular drifts section
Authors: PANG Huandong, CHEN Shihai, GAO Wenle
PP: 1749-1753
Abstract: In this paper, according to the characteristic of the displacement potential function of the blasting vibration wave, by the method of separation of variables, the motion law of confining rock particle in axis coordinates is derived, and the rule between stress and axial distance, radial distance and time has been worked out. The general blasting gas pressure is conducted as boundary condition, which acts upon the wall of confining rock, and the amplitude parameter of the stress has been given. The result suggests that the internal stress in confining rock caused by blasting vibration wave decreases very quickly and different stresses are proportional to the power of minus 1/2, 3/2, 5/2 in distance respectively, as well as declines with the negative exponent of time and radial distance. At the same time, the factors which affect the stress are radius of blasting cavity, condition parameters of confining rock, and the anisotropy caused by them.
Keywords: sinking and driving engineering; confining rock; wave equation; separation of variables
 
Title: Reservoir real-time optimization with constraints based on variational theory
Authors: ZHANG Kai, LU Ranran, ZHANG Liming, YAO Jun, LI Xiaoxue
PP: 1739-1748
Abstract: Reservoir is recognized as a complex dynamic system in this research. An optimal mathematical model of reservoir production is established, the goal of which is to maximize net present value of production. Combining with maximum principle, the corresponding adjoint model is deduced and solved high-efficiently to obtain optimal production schedule. Because the optimized object here is the development of oil field, it must relate to some constrained conditions such as the boundary limits of a single well and the total injection rate of reservoir block etc. To solve these problems, the paper used logarithmic transformation and the average gradient method to realize constrained production optimization. Based on the above theoretical study, applied examples of reservoir are analyzed. The results show that the obtained optimal production scheme is coincident with the demand of actual field and it will provide a strong theoretical basis and technical support for smart field system.
Keywords: oil and gas field development project; smart field; production optimization; adjoint model; constrained optimization
 
Title: Numerical studies on heat transfer and friction factor characteristics of discrete inclined ribs tubes
Authors: SHI Kun, LIU Wei, LIU Zhichun
PP: 1733-1738
Abstract: In this paper, a research on the heat transfer tube which is used widely in shell and tube heat exchanger was performed. The fluid flow resistance was tried to be reduced to improve the heat transfer performance. According to discrete double-inclined ribs tube (DDIR), which had been mentioned in the existing literature, heat transfer tube with cross inclined ribs was designed. Then, in order to minimize the flow resistance, and improve the overall heat transfer performance, the model design method was improved from three aspects: 1) Inclined ribs arrangement circumferentially was changed to parallel; 2) Inclined ribs arrangement along the flow direction was changed to staggered; 3) The way how the inclined ribs plunged into the wall surface was changed from both ends deep to gradually deepening. Numerical calculation on laminar flow was conducted, and the results were compared. The numerical results of different kinds of models were compared, and the results show that the inclined ribs in a gradual deepening mode can effectively reduce the flow resistance, and improve the overall effect of heat transfer.
Keywords: energy-saving technology; heat transfer enhancement; inclined ribs; performance evaluation criteria; efficiency evaluation criteria; numerical simulation
 
Title: Study of intercepting effect on the oxygen molecules in the“Diabolo-shaped” magnetic field space
Authors: ZHANG Shiping, REN Han, WU Ping, WANG Li
PP: 1727-1732
Abstract: Based on the concept of “magnetic-sieve”, the magnetic field distribution in the “Diabolo-shaped” magnetic field space was simulated by ANSYS finite element software. The results showed that the intercepting effect on oxygen molecules was enhanced in the “Diabolo-shaped” magnetic field space. Multi-channel cascading magnets’array not only enhanced the “magnetic-sieve” effect in each channel, but also improved the ability of air flow processing effectively. By introducing and magnetic yoke, the central magnetic flux density was increased, consequently, the intercepting effect on oxygen molecules by “magnetic-sieve” was enhanced, meanwhile, the difference of intercepting effect on oxygen molecules between each channel in multi-channel cascading magnets’array was eliminated.
Keywords: energy-saving technology; oxygen and nitrogen separation; gradient magnetic field; magnetic-sieve; intercepting effect on the oxygen molecules; multi-channel cascading magnets’ array
 
Title: System design and implementation of oil production trends forecast
Authors: YAO Jiming, GUO Wenxue
PP: 1721-1726
Abstract: Through the analysis of various influence factors, the paper constructed a forecasting model combining GM(1,1) with BP artificial neural network to predict the short-term trends of oil production, and used the Weng’s cycle model to predict the medium-and long-term trends. Based on this, a general trend forecast software of oil production was intruduced. This software system was designed with Visual C++6.0 in Windows platform, combined with the database of Access and the technology of activex data objects (ADO). The paper stated the design conception of the system and operation method of the main modules.
Keywords: energy calculation and measurement; petroleum; forecast; computer soft; database
 
Title: Analysis on aerodynamic characteristics of blunt trailing edge wind turbine airfoil
Authors: CHENG Xiaolong, MA Chaochen, LAO Dazhong, WANG Leilei, YANG Ce
PP: 1714-1720
Abstract: In this paper, a blunt trailing edge wind turbine airfoil TR-4000-2000 was numerically investigated by the computational fluid dynamics software FLUENT in the case of k-ε turbulent model, and the influence caused by the use of blunt trailing edge on aerodynamic characteristics were studied. Steady and unsteady numerical simulation of airfoil flow field in different attack corner was performed, and the fluctuation characteristics of aerodynamic parameters was obtained, such as lift coefficient, drag coefficient and time-dependent pressure on airfoil surfaces. Besides, the periodic movement of shedding vortex and separation vortex was gained, and the corresponding relationship between fluctuation of lift coefficient, drag coefficient, trailing edge vortex movement and surface pressure fluctuation was determined by the way of frequency analysis. The analytic results showed that the pressure fluctuation on airfoil surface caused by shedding vortex in trailing edge was the main reason of aerodynamic characteristic fluctuation. Based on these researches, an overall explanation was given to the characteristics of fluid field and its transformation rules, which built the foundation for further research such as lift improvement and drag reduction, stall control and flow control.
Keywords: wind energy; blunt trailing edge airfoil; numerical simulation; lift and drag characteristic; pressure fluctuation
 
Title: Microstructures and properties of aluminum reflector
Authors: YANG Fan, LIU Jingjing, XU Longfei
PP: 1709-1713
Abstract: In this paper, the microstructures and properties of indoor and outdoor aluminum reflector for concentrated solar system were investigated by means of scanning electron microscopy (SEM), X-ray diffraction (XRD) and UV/VIS reflection/transmission measurement apparatus. The anti-friction and performance of the protective superficial layers of reflector were quantitatively evaluated by HV hardness test and optical observation. The results showed that the surface of aluminum reflector was consisted of single or double protective film with amorphous structure. The pressure distortion and the crack image of aluminum membrane surface proved that outdoor reflector had good superficial wear-resisting performance.
Keywords: solar energy; aluminum reflector; microstructure; reflectivity
 
Title: Growth behavior prediction of pitting corrosion depth for oil and gas pipelines based on LS-SVM
Authors: CHENG Guangxu, LI Jun, FAN Zhichao
PP: 1699-1708
Abstract: In this paper, a pitting corrosion depth time series prediction model for oil and gas pipelines, namely least squares support vector machine (LS-SVM) model, is established based on LS-SVM. As for the complex situation of the parameter optimization process in LS-SVM model, a hybrid particle swarm optimization (HPSO) algorithm is presented by the introduction of the modified initialization of particle positions, self-adaptive inertia weight and modified velocity updating equation to improve the parameter optimization ability of particle swarm optimization (PSO). The simulation experiment indicates that HPSO algorithm has stronger search ability and higher convergence precision than standard PSO algorithm. The calculated results of an engineering case show that LS-SVM model performs a better prediction performance when comparing with GM(1, 1) model, auto-regression moving average (ARMA) model and BP neural network (BP-NN) model.
Keywords: oil and gas energy; oil and gas pipelines; pitting corrosion depth; least squares support vector machine; parameter optimization