Volume 37,Issue 9,2014 Table of Contents

1 A novel viscoelastroplastic constitutive model of rubber materials and parameter identification

ZUO Shuguang , ZHU Junxing , WU Xudong , HU Jing , DUAN Xianglei

2014, 37(9):1-10. DOI: 10.11835/j.issn.1000-582X.2014.09.001

[Abstract](1884) [HTML](443) [PDF 12.53 M](1507)

Abstract:
The plastic unit with a yielding process is used to describe rubber’s amplitude-related characteristic, and the method to identify the number of plastic unit and the distribution of the yielding point is researched. A novel hyperelastic-viscoelastic-plastoelastic constitutive model of rubber is built and its parameters are identified according to the results of the rubber material property experiments. The theoretical model is transfered into the material parameters of rubber in the finite element software, which are used to create the finite element model of rubber material. Finite element simulation results of rubber are in good agreement with the experimental results, so the model can be used for subsequent modeling of rubber bushing and analysis of suspension system.

2 Influence numerical analysis of combustion chamber thermal boundary conditions on unsteady combustion characteristics in micro ICE

TANG Gangzhi , ZHANG Li , DU Baocheng , SHANG Huichao

2014, 37(9):11-17. DOI: 10.11835/j.issn.1000-582X.2014.09.002

[Abstract](1996) [HTML](739) [PDF 7.38 M](1382)

Abstract:
To research the influence of combustion chamber thermal boundary conditions on micro combustion characteristics in micro ICE, the laminar flow finite rate model is adopted to simulate the micro combustion process. Firstly, the influence of grid scale, the time step length and the maximum iterations per time step on accuracy of simulation results are explored. The results show that simulation results agree well with experimental results. And then, the influences of heat transfer coefficient, wall thickness and material on combustion characteristics are discussed. The results indicate that heat transfer coefficient has obvious influence on combustion characteristics. The pressure rise rate decreases, the ignition delays and the highest pressure value drops 2 atmospheres as heat transfer coefficient increases from 0 to 55 W/(m 2·K). The wall thickness and material have a little effect on combustion characteristics. This is because that the main heat transfer resistance in the heat flow path from cylinder to external environment lies between the outer wall and environment.

3 Unbalance response analysis of high speed aerostatic motorized spindle rotor system

YU Lihua , XIE Qingsheng , LI Shaobo , HUANG Haisong

2014, 37(9):18-25. DOI: 10.11835/j.issn.1000-582X.2014.09.003

[Abstract](1338) [HTML](506) [PDF 8.84 M](1453)

Abstract:
According to the high speed of aerostatic motorized spindle, the complex dynamic behavior and the unbalance incentive, dynamical model is built up on the basis of Lagrange equation. And it is includes the differential equatioan of free vibration and forced vibration.Then, the residual unbalanced inertial centrifugal force and the mechanism of unbalanced magnetic pull are analyzed. Finally, a motorized spindle rotor-gas bearings system with the highest working speed of 250 000 r/min is simulated in the way of the unbalance excitation harmonic analysis. The dynamic behavior of high-speed aerostatic motorized spindle is revealed in supercritical mode at unbalance excitation.A theoretical basis is provided for the optimization design, vibration control to the rotor system of high-speed aerostatic motorized spindle in engineering application.

4 Dirt treatment by high-frequency electromagnetic pulse for circulating cooling water and thermal resistance monitoring system

YANG Zikang , XIONG Lan , FU Keqin , MIAO Xuefei

2014, 37(9):26-33. DOI: 10.11835/j.issn.1000-582X.2014.09.004

[Abstract](1426) [HTML](309) [PDF 8.85 M](1302)

Abstract:
The circulating cooling water systems of heat transfer equipment generates dirt easily in high temperatures. Dirt will not only reduce thermal efficiency of heat exchange equipment, but also affect the equipment safety. This paper sets up a platform of miniature water cycle based on the real structure of industrial circulating water, uses high-frequency pulse treatment method to act on calcium carbonate in circulating cooling water of manual configuration, observes the impaction of blank group and different frequencies of high frequency electromagnetic pulse groups on fouling in cooling water, and monitors the thermal resistance of cooling water by a designed thermal resistance monitoring system. The results show that the high-frequency electromagnetic pulse treatment plays a very good anti-scaling effect on circulating cooling water, because both the conductivity decline trend and pH rising trend of water becomes slow. According to the thermal resistance data of analog exchanger, thermal resistances of high frequency processing groups are less than that of blank group. Moreover, it further confirms the important role of anti-scaling for high-frequency electromagnetic pulse.

5 Research and design of a solar charging system based on FPGA

CHENG Hongli , ZHANG Gengchuan

2014, 37(9):34-39. DOI: 10.11835/j.issn.1000-582X.2014.09.005

[Abstract](1426) [HTML](396) [PDF 6.55 M](1057)

Abstract:
In order to meet the special application requirements of photovoltaic power system for contamination monitoring system in high voltage transmission line, this paper presents a charging system suitable for fast charging of supercapacitor with low-power solar cells. This design uses BUCK-BOOST circuit as the main charging circuit topology, uses a novel MPPT tracking method, Weighted Variable-Step Voltage-Hysteresis Perturbation & Observation MPPT(WVV P&O MPPT), and achieves control by FPGA. The system’s configuration and control strategy are theoretically verified by Matlab/Simulink, and the production and testing of the charging system are completed. Test results show that the charging system uses low-power solar cells and charges 2F and 5F super capacitors under normal weather conditions, and all of these charging works can be finished during a relatively short time. Compared with the previous research of our task force, this design effectively reduces the charging time and improves the utilization of solar energy.

6 Lossless data hiding with ranks transform

YANG You , ZHAI Hao , YU Ping

2014, 37(9):40-46. DOI: 10.11835/j.issn.1000-582X.2014.09.006

[Abstract](1700) [HTML](329) [PDF 6.79 M](1285)

Abstract:
For taking full advantage of carrier image's pixel correlation, a lossless data hiding algorithm with ranks transform (LDHA_RT) is proposed. Along with three directions of column, row and diagonal, the pixel difference images and their histograms are calculated one after another. The obtained pixel difference histograms are shifted to construct the redundancy spaces, so that the hiding information could be embedded in a designated position. After the hiding data is extracted, the carrier image could be recovered reversibly without any additional information. The experiments demonstrate that the PSNR/bits of the LDHA_RT is the lowest or close to the lowest, compard with these algorithms mentioned in the references. This implies that the LDHA_RT has large capacity of hiding data under a good image quality.

7 Simulation research on oxygen blast furnace ironmaking process

WANG Chengshan , SHI Yanwen , LI Dandan , YANG Yazhou , MU Xiaojing

2014, 37(9):47-58. DOI: 10.11835/j.issn.1000-582X.2014.09.007

[Abstract](1666) [HTML](337) [PDF 10.55 M](1227)

Abstract:
A system simulation mathematical model on oxygen blast furnace ironmaking process is established. Provided that the material composition and the values of necessary process parameters are given, the model can predict the consumptions of raw material, fuel and flux, the quantity and composition of slag, the quantities and components of all kinds of gases, etc. At the condition of 90% stack ore metallization, the calculated results of the model show that when more circulating gas are introduced into the stack, the heat controls the total gas for the stack ore reduction, while when more circulating gas are introduced into the hearth, the reductive components control the total gas for the stack ore reduction. At normal operations with coke rate fixed, the coal consumption linearly increases with the output top gas. When the coke rate is fixed at 200 kg, the minimum value of calculated coal rate is 200 kg or so.

8 Numerical study of airflow distribution in air-conditionedtrain in Qinghai-Tibet Railway

WANG Ye , XU Ran

2014, 37(9):59-67. DOI: 10.11835/j.issn.1000-582X.2014.09.008

[Abstract](1566) [HTML](347) [PDF 9.07 M](1249)

Abstract:
To obtain the influence of outer environmental condition on the indoor airflow distribution for the 25T air-conditioned train in Qinghai-Tibet, the Realizable k-ε model is adopted to numerically analyze the indoor temperature and velocity fields of the running train. The results indicate that solar radiation has great effect on the indoor temperature field and it is meaningful for improving the thermal comfort to adjust the air supply parameters with the outer environmental condition. Under different air supply conditions, it is the conjugating relation between the indoor temperature field and velocity field that leads to different thermal comfort in different regions of the running train. In addition, the operating modes exchange under different outdoor environmental conditions is also discussed and some additional functions of the using air-conditioning system are put forward too.

9 Seismic response of site conditions to Xigeda formation of Xichangthree-dimensional subgrade

CHEN Jipu , XU Zemin , ZHANG Jiaming , LIU Wenlian

2014, 37(9):68-76. DOI: 10.11835/j.issn.1000-582X.2014.09.009

[Abstract](1621) [HTML](432) [PDF 9.00 M](1040)

Abstract:
In order to find out the effect of site structure and distribution of cut-fill area on the seismic responses rules of Xigeda formation three-dimensional subgrade in Xichang, finite element method software is used to simulate the acceleration distribution on the surface of three-dimensional calculation models under seismic load. This paper discusses differences of subgrade seismic response from three aspects, including platform structure of the site, elevation mutation, and excavation and filling area. And there are four conclusions can be drawn. Firstly, the higher the elevation sites platform is，the greater the acceleration amplification factors are，especially in the changes of vertical acceleration amplification factors. Secondly, a sudden increase of elevation causes a sudden increase of vertical acceleration magnification factors, and acceleration amplification factors is getting smaller while extending to the platform inside. Thirdly, the acceleration amplification factors of filled area are greater than those of the excavation area. Fourthly, because terrain amplification of the seismic response is directional, three-dimensional calculation models should be used to numerical analysis. The results provide an important basis for the Xigeda subgrade base plan selection in Xichang and seismic design.

10 The assessment of corrosion and damage of reinforced concretestructures in marine environment

JIANG Xiangyang

2014, 37(9):77-83. DOI: 10.11835/j.issn.1000-582X.2014.09.010

[Abstract](1400) [HTML](299) [PDF 6.04 M](1222)

Abstract:
This paper analyzes the failure modes of reinforced concrete structures in marine environment, which is mainly influenced by the chloride ion erosion. Under the action of chloride ions, reinforced steel bars are corroded seriously, leading to cracking. We carry out this process in detail, evaluate the amount of corrosion, and then establish a cross-sectional area model of steel corrosion. Based on Fick’s law, the quantified treatment of chloride ion penetration, critical concentration, and diffusion coefficient, etc. are processed. We establish the deterioration model of steel with resistance deterioration, and analyze the reliability of the reinforced concrete structures.

11 Automatic method for aircraft target recognition in remotesensing images based on improved active shape model

GAN Shoufei , SUN Hao

2014, 37(9):84-91. DOI: 10.11835/j.issn.1000-582X.2014.09.011

[Abstract](1322) [HTML](338) [PDF 8.68 M](1147)

Abstract:
We propose an estimation method for aircraft target direction based on histograms of oriented gradients (HOG), and then use the improved active shape model (ASM) to model the deformation between the different types of targets. Finally, we use kernel density estimation method (KDE) global statistical shape constraint to obtain the target to achieve the target recognition, and design a semi-automatic image feature point detection strategy for aircrafts, which improves the efficiency of training samples for calibration feature points. Recognition experiments on aircraft remote sensing images show the proposed method can better recognize aircraft targets than the existing methods.

12 Multi-target tracking algorithm based on adaptive sampling interval in wireless sensor networks

WANG Jianping , ZHAO Gaoli , HU Mengjie , CHEN Wei

2014, 37(9):92-99. DOI: 10.11835/j.issn.1000-582X.2014.09.012

[Abstract](1519) [HTML](307) [PDF 7.88 M](1342)

Abstract:
Multi-target tracking is a hot topic of current research on wireless sensor networks (WSN). Based on adaptive sampling interval, we propose a multi-target tracking algorithm in order to save energy consumption and prevent tracking lost for WSN. We contrast the targets moving model by using the position metadata, and predicte the targets moving status based on extended Kalman filter (EKF).we adopt the probability density function (PDF) of the estimated targets to establish the tracking cluster. By defining the tracking center, we use Markov distance to quantify the election process of the main node (MN). We comput targets impact strength through the targets importance and the distance to MN node, and then use it to build tracking algorithm. We do the simulation experiment based on MATLAB, and the experiment results show that the proposed algorithm can accurate predict the trajectory of the targets, and adjust the sampling interval while the targets were moving. By analyzing the experiments data, we know that the proposed algorithm can improve the tracking precision and save the energy consumption of WSN obviously.

13 Copper coatings crystal orientation under the influence of additivesMPS, SPS and their combinations with PEG and Cl -

WEI Zeying , WANG Wenjing

2014, 37(9):100-105. DOI: 10.11835/j.issn.1000-582X.2014.09.013

[Abstract](2514) [HTML](568) [PDF 5.20 M](1604)

Abstract:
Highly preferred orientation copper coatings show excellent functions. Many factors affect copper coatings’ crystal preferred orientation, and additives are one of the factors. Copper coatings were prepared at 0.040 A/cm 2 and 0.150 A/cm 2 by constant current, respectively. The electrolytes were acid CuSO4 solution with additives MPS (3-mercapto propane sodium sulfonate) or SPS(poly-2-sulfur-2-propane sodium sulfonate), and their combinations with PEG (polyethylene glycol) and Cl -. X-ray diffraction shows that (220) lattice plane fully preferred orientation is obtained at the higher current density 0.150 A/cm 2 with the combination of MPS+Cl - or SPS+Cl -. But different preferred orientations are obtained with only MPS or SPS, or other combinations, such as MPS+PEG, MPS+PEG+Cl -, SPS+PEG, SPS+PEG+Cl -. Using different combinations of additives is an effective method to obtain highly preferred orientation lattice planes earlier in the process of electrodeposition.

14 Gas desorption inhibitory effect of coal in low temperature environment

WANG Zhaofeng , YUE Gaowei , KANG Bo , XIE Ce

2014, 37(9):106-112. DOI: 10.11835/j.issn.1000-582X.2014.09.014

[Abstract](1839) [HTML](317) [PDF 6.20 M](1476)

Abstract:
Gas loss is serious in current coal core method, and freezing core technology will become a new direction for gas content determination in the future, so it is the key to study gas desorption characteristics in low temperature environment (below 0℃). Therefore, in this paper, a self-made high/low temperature gas adsorption/desorption device is used to test gas desorption laws in low temperatures (-10, -20 and -30 ℃). The tested results show that the effect of temperature on gas desorption is very obvious. When temperature decreases, gas adsorption quantity increases; while gas desorption quantity decreases as temperature decreases. Lowering temperature suppresses gas desorption. And the lower the temperature is, the more obvious the gas desorption inhibitory effect is. Increasing gas pressure weakens gas desorption inhibitory effect in low temperature environment.

15 Mechanical control effect of hard tectonic structure on coal seam gas flow

ZHANG Chunhua , ZHANG Weiliang , WANG Jiren

2014, 37(9):113-118. DOI: 10.11835/j.issn.1000-582X.2014.09.015

[Abstract](1335) [HTML](347) [PDF 6.70 M](1133)

Abstract:
To analyze the controlling effect of hard tectonic structure to gas flow at the coal seam heading face, two physical mechanical models are established, normal coal seam driving and hard body embedding coal seam driving. Then according to the above two numerical models, it numerically analyzes the stress distribution characteristics, the coal seam permeability change and the gas flow rule at the coal seam heading face by using rock fracture finite element software RFPA 2D-GAS with solid-gas coupling analysis module, and carries on comprehensive comparative analysis. Finally, combining with two ordinary cases from product field, it verifies the conclusion from the numerical simulation that the concentrated stress influences the coal seam permeability and controls the gas flow. The results show that: the concentrated stress at the coal heading face with hard tectonic structure is like a “closed gate”, as it makes the coal seam permeability obviously lower and blocks the normal migration of gas in the vicinity to the freedom space. In order to eliminate the gas abnormal emission threat at the high gassy coal seam heading face, stress and gas relief measures must be taken to rip the “closed gate” and effectively remove the concentrated stress to provide safe releasing channels for the blocked gas.

16 Clogging mechanical model and its application in gas extraction borehole

WANG Yonglong , SONG Weibin , SUN Yuning , ZHAI Xinxian , WANG Zhenfeng

2014, 37(9):119-127. DOI: 10.11835/j.issn.1000-582X.2014.09.016

[Abstract](1285) [HTML](250) [PDF 8.37 M](1093)

Abstract:
A clogging segment mechanical model is established on gas extraction horizontal borehole. Based on the air pressure extremes pmax of the construction site, we solve the corresponding critical clogging length L0 and find clogging will occur when L> L0. With the clogging segment mechanical model, we analyze the calculation method of the retreat drilling rod resistance in borehole. The influence rule of clogging length and air supplying system pressure on retreat drilling rod resistance is analyzed. Analysis results show that the main reason for difficult drilling clogging and retreat drilling rod is the higher pressure in borehole clogging segment. The retreat drilling rod resistance is especially sensitive to the change of air supplying system; therefore, the effective method of reducing the retreat drilling rod resistance is reducing the air supplying system pressure in borehole. The drilling construction status in Jiulishan coal mine is analyzed by using the clogging segment mechanical model, and three technical measures are put forward, including increasing slagging space, reducing slagging resistance and increasing drilling rod strength. When the improving measures are adopted, the pipe-sticking phenomena decreases, the drilling rod broken phenomenon are averted and the drilling efficiency increases by 17%.

17 Optimization research on leaving an “island” and building a bridge through non-coal-zone in surface coal mine

BAI Runcai , FU Ensan , LIU Guangwei , ZHAO Chen

2014, 37(9):128-135. DOI: 10.11835/j.issn.1000-582X.2014.09.017

[Abstract](1659) [HTML](547) [PDF 7.84 M](1187)

Abstract:
Non-coal-zone in surface coal mine usually causes invalid stripping and increases stripping ratio. In order to solve the problem of increased stripping ratio and transportation distance, and overcome the connection difficulty of coal amount, a new method of leaving an “island” and building a bridge is put forward. A systematic study is made on the optimization transportation system of building a bridge behind the island. At the same time, the procession of building and taking down the bridge and accelerating the path is simulated, and measures for production capacity connection are put forward. The simulation achievements are applied to Shenhua Beidian surface coal mine and the results show that leaving “islands” and building bridges project can reduce the stripping ratio and transportation costs. Moreover, the economic benefit can be improved.

18 Seismic identification method of deep thin sand shale interbedding

YANG Fei , HUANG Cheng , LI Pengfei , GUI Hongbing

2014, 37(9):136-143. DOI: 10.11835/j.issn.1000-582X.2014.09.018

[Abstract](1326) [HTML](312) [PDF 11.67 M](1590)

Abstract:
The deep interbeds of sand and shale reservoir is a kind of typical low porosity and low permeability reservoir, which generally has the characteristics of deep burial, rapid lateral variation, and deep physical difference, etc. The traditional thin layer quantitative description method can only identify the stratigraphic whose thickness is less than λ/4, and it’s difficult to realize fine interpretation. Therefore, the paper firstly uses inversion joint prediction techniques to establish geological models for wave equation forward, and then analysis the target layer’s characteristics of seismic wave field from the forward angle. Finally, we apply wave impedance inversion that is based on forward modeling results to make quantitative analysis for inversion sand’s horizontal and vertical distribution characteristics. The results show that the seismic identification method which is based on forward model can not only unleash the advantages of seismic horizontal distribution, but also improve the accuracy of interpretation in the vertical direction. And the results can provide references for identifying deep thin sand shale interbedding reservoirs in Qianliyuan area.

19 EPC contract dispute alert and case analysis

LIU Hu , HUANG Xiaolong

2014, 37(9):144-150. DOI: 10.11835/j.issn.1000-582X.2014.09.019

[Abstract](1386) [HTML](424) [PDF 6.06 M](1319)

Abstract:
When the EPC contract dispute occurs, complex relationship is usually involved, contract claim amount is large, and the consequence of hindering a contract is serious. Therefore, in order to prevent, warn and track disputes, based on some information with strong signs showing disputes, this study establishes a case based reasoning and rule based reasoning (CBR+RBR) model with qualitative and quantitative integration by synthetically using reasoning theory, rough set theory, the entropy method and Euclidean distance retrieval method to prevent and warn possible disputes and realize real-time tracking. By collecting related cases and establishing case databases, we use the CBR+RBR model to analyze various factors may cause EPC contract disputes, and through case analysis to validate that the model can warn EPC contract disputes.

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