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ISSN 1674-2850
CN 11-9150/N5
 
Current Issue
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August 30,2012
Volume 5,Issue 16
Pages -
Subject Area:Engineering Thermophysics,Electrical Engineering,Industrial Robot Technology
 
Title: Spectral control characteristics of radiator with microstructure
Authors: SHUAI Yong, CAO Liangdan, YANG Guo
PP: 1582-1589
Abstract: The present paper is concerned with plasma dispersion relations for tungsten grating surface, and the finite-difference time-domain method is adopted to study the effect on radiative characteristics of microstructure due to the microcavity resonance and the surface plasmon polaritons (SPPs). Parameter studies on key performances variables, such as geometry dimension, spectrum and polarization, are analyzed on emission characteristics of the radiator with microstructures. A radiator with rectangular array structures of square holes is optimized the geometry design with well emission performance at the spectral response band. The results show the important theory significance and practical application value in designing the radiator of the thermo-photo-voltaic (TPV) cell.
Keywords: engineering thermophysics; thermal radiation; microstructure; spectral control; thermo-photo-voltaic cell
 
Title: Research on physical properties of diesel-gasoline blend fuel
Authors: BAO Tangtang, ZHOU Bo, LI Tian, DENG Jun, WU Zhijun
PP: 1575-1581
Abstract: Physical properties including density, viscosity, surface tension and the stability of the different contents of diesel-gasoline blend fuel parameters were measured and analyzed. The experiments were performed on the diesel-gasoline blend fuel with 4 different volume fractions of diesel (20%, 40%, 60%, and 80% respectively) at temperature from 5 to 65℃. Based on experimental data, the influence of temperature and diesel content on the blends properties was summarized and the formulas for the material parameters were determined. In addition, a database of the material parameters of the blends was established.
Keywords: internal combustion engine engineering; diesel-gasoline; blend fuel; physical properties
 
Title: Study of doubly-fed wind power generation control strategy based on variable speed constant frequency
Authors: LIU Lecao, ZONG Weilin
PP: 1568-1574
Abstract: Doubly fed induction generator (DFIG) uses variable speed constant frequency (VSCF) technology, and realizes four quadrant operation with adjustable power factors to doubly-fed wind power generator though rotor side AC-DC-AC converter. The converter adopts pulse width modulation (PWM) strategy at rotor side and grid side, and uses current inner loop, speed outer loop and voltage feedforward decoupling control. By Matlab simulation, the paper analyzes the speed regulation tracking and load disturbance resistance performance, and demonstrates the effectiveness of the control strategy.
Keywords: electrical engineering; pulse width modulation; variable speed constant frequency; doubly-fed wind power generation
 
Title: Control system design of resolver as speed sensor for dual mechanical ports electrical machine
Authors: XU Qiwei, CUI Shumei, KUANG Zhi
PP: 1563-1567
Abstract: This paper focused on the speed sensor requirements of dual mechanical ports machine control system for hybrid electric vehicle. Magnetic reluctance resolver with good robustness was chosen as the speed sensor. The principle of magnetic reluctance resolver was analyzed, and then the excitation circuit and decoding circuit were designed based on AD2S1200. At last, the speed signal was gotten by the serial communication between DSP TMS320LF2407 and AD2S1200, and the experiment results proved the correctness and rationality of the design.
Keywords: electrical engineering; dual mechanical ports electrical machine; resolver; AD2S1200
 
Title: Driver design for snake-like life detector
Authors: ZHENG Yuanfei, BAO Tianzhe, ZHU Chunli, WANG Yangsen, WU Xianghua
PP: 1559-1562
Abstract: The research designs and manufactures the underwater driver of the snake-like detector, and through the innovative transformation of an ordinary wheel, it makes the driver work on land like an ordinary wheel and work underwater like a propeller. That is to say, the driver can make flexible movement in those two types of different natural environment. And by using the 51 singlechip and CAN bus as control system, the research tries to expand the usage of the snake-like robot and maximize its specific advantages.
Keywords: mechanical design; snake-like detector; amphibian; drive system
 
Title: Study on vocal element simulation of piezoelectric bone conduction hearing device with square structure
Authors: LIU Jie, GAO Yingying, ZENG Ping, CHENG Guangming
PP: 1553-1558
Abstract: The paper uses square piezoelectric oscillator of intermediate fixed support-type as vocal element of the bone conduction hearing device, uses ANSYS to build finite element model of the square piezoelectric oscillator of intermediate point fixed support-type and intermediate line fixed support-type, then applies static analysis, modal analysis and harmonic response analysis on the two different support-types. Thus to provide theoretical basis for further study of the bone conduction hearing device that uses square piezoelectric oscillator of intermediate fixed support-type as vocal element.
Keywords: mechanical design; square piezoelectric oscillator; simulation; bone conduction
 
Title: Analysis on contact performance of real machined surface based on finite element method
Authors: ZHOU Siquan, LI Yan, LI Pengyang, WEI Chunmei
PP: 1547-1552
Abstract: Firstly, this paper solves the problem by measuring the profile of the machined surface, processing the position data, inputting the position data to finite element software directly by ANSYS parameter design language (APDL) programming and creating the solid model of the real rough surface. Then it statically analyzes the contact between the rough surface and a rigid flat plane and gets the relation of contact area, load, pressure, deformation and so on. The results show that the simulation has good effect. Contact deformation exponentially increases with contact pressure, and downward normal contact stiffness exponentially increases with average pressure.
Keywords: mechanical friction, attrition and lubrication; contact performance; real surface; finite element analysis
 
Title: Constraint value stream mapping and its application in a chip set assembling line
Authors: YANG Zheng, YANG Yu, BAO Beifang
PP: 1538-1546
Abstract: In order to solve the problems accrued during self improvement of electronic manufacturers, a production system improvement mode based on constraint value stream mapping (CVSM) has been proposed. This paper optimizes the value stream mapping (VSM) tool and hammers out CVSM tool, so as to combine lean think and theory of constraints (TOC) aiming at optimizing the production system for research purpose. A typical production system has been chosen to study the implementation of CVSM tool in real circumstances. An application of the CVSM has been performed in a chip set assembling line to lay down an improvement scheme. The application process and related management control has been cleared. The effects have been evaluated, which provide a reference for electronic manufacturers and enterprises in other fields in China.
Keywords: other subjects of mechanical engineering; value stream mapping; theory of constraints; lean thinking; production system
 
Title: Cold copper surface freezing characteristic test
Authors: JIN Jingfu, CHEN Tingkun, LI Weiwei, CONG Qian
PP: 1533-1537
Abstract: According to the shortcomings of the evaluation criteria of ice strength,the material surface ice strength test device was made, and the copper strength test was carried out. The results show that the device can ensure repeatability and reliability test, but also truly reflect the properties of icy material strength. Copper icy strength experiments show that the ice strength increases with the decreasing temperature of cold surface and presents fast-sags-slow process with the freezing time. The microscopic observation analysis shows that: the sags of icing intensity is because the freezing volume expansion caused the freezing interfacial shear stress changing, and extension and covering of the surface frost caused the destruction and reorganization of the interfacial layer. Initial interface layer near the back of the frost layer melting and icing is dominated by the influence of the interfacial layer.
Keywords: other subjects of mechanical engineering; adhesion strength of ice; copper; experimental test; evaluation methodology
 
Title: Study of laser welding technology about hastelloy alloy and its weldability
Authors: WANG Zhuo, WANG Yunshan, JIA Tiantian
PP: 1524-1532
Abstract: In this paper, orthogonal test design method is used to design the orthogonal table which according to the influence factors in the welding process and the level of each influence factor, and find out each combination level of the welding process. According to this combination level, a robot laser welding system is used to research on Hastelloy C-276 alloy thin-walled tube with a thickness of 0.8 mm, and a robot laser welding system is used to perform a great deal of experiment. By observing the surface topography of the welding seam joint, this paper verifies the feasibility of the welding method that uses robot laser welding system to weld this material, does the tensile test about the specimen which has better weld morphology, and optimizes the influence factors in the welding process to find the most reasonable welding plan. The paper provides certain technical support to the application of hastelloy alloy.
Keywords: special processing technology; laser welding; wledability; orthogonal test design; hastelloy alloy; tensile test
 
Title: Multi-objective optimization of shielding effectiveness of propulsive wheel based on the approximate model method in iSIGHT platform
Authors: LUAN Yukun, WANG Kaifeng, XU He
PP: 1515-1523
Abstract: This paper collects the simulation data of the electromagnetic shielding effectiveness in the propulsive wheel, which were imported from Ansoft HFSS software to iSIGHT software in order to build relationships between physical parameters of the propulsive wheel and shielding effectiveness, which is based on radial basis function (RBF) neural network. The design variables are determined by analyzing the design of experiment (DOE), which focuses on the main effects and Pareto contribution rate of its physical parameters on shielding effectiveness, then the multi-objective optimization is used to optimize its standards of shielding effectiveness. The paper draws a conclusion from the optimization results of shielding effectiveness: considering that the round holes have a great effect on shielding effectiveness, the effective method to improve the shielding effectiveness is to reduce the specification of holes.
Keywords: industrial robot technology; mobile robot; multi-objective optimization; propulsive wheel; iSIGHT
 
Title: Filter design for signal acquisition in MCU system based on Matlab toolbox
Authors: XU Jingbo, WANG Desheng, LI Shilei, GUO Shengli,YAN Shiqi, MENG Yang
PP: 1509-1514
Abstract: In order to effectively reduce the noise interference to the data acquisition channel of micro controller unit (MCU) system, this paper makes use of the powerful functions of Matlab toolbox to help the filter design. Based on the deduced filter coefficients, the filter model is established which is translated into the corresponding digital filter algorithm. Through Simulink toolbox, the interrupted signal source is simulated and the performance of filter is verified. That solves the filter design difficulties in MCU system and improves development efficiency.
Keywords: measuring and testing technologies and instruments; filter design; Matlab toolbox; micro controller unit system; anti-interference
 
Title: Static analysis of mechanical draft counter-flow coolingtowers’ frame structure
Authors: MA Kun, GAO Ding
PP: 1503-1508
Abstract: Due to the structural characteristics of the cooling tower associated with the quality features and usage characteristics, and based on the considerations of the reliability, stability, and security of the cooling towers structure, this paper analyzes the frame structure of mechanical draft counter-flow cooling towers, uses Pro/E software to establish its three-dimensional solid model, and then uses ANSYS Workbench 12.0 software for the frame structure’ static analysis after the wind load is calculated. The results show that the wind load has an influence on the frame structure of cooling tower, which needs to be configured with a certain process for its improvement.
Keywords: mechanical manufacturing automation; cooling tower; counter-flow; frame structure; static analysis
 
Title: Numerical analysis on complex mechanism about free abrasive ultraprecision surface machining of copper interconnection layer
Authors: HAN Xuesong
PP: 1499-1502
Abstract: Large-scale classical molecular dynamic simulation of tribology interaction among nanoparticles and solid surface and the surface morphology have been carried out to investigate the complex physical essence of surface planarization. The results show that simultaneous impact of several abrasive particles or the repeated impact of abrasive particles leads to material failure. The results also justify that no single wear mechanism dominates all operating conditions, different wear mechanisms operate, with their relative importance changing as the sliding conditions change. The velocity and angle of approach of the abrasive particles will determine the kinetic energy that the particles transfer to the surface, and hence will affect removal rates. The real finished nanometric surface should be the mathematical integration of numerous discrete areas but not a continuous smooth integrity at atomic level.
Keywords: mechanical manufacturing automation; chemical mechanical polishing; numerical analysis; molecular dynamics; complex behavior
 
Title: Vibration response analysis of a rotor system based on Hertz contact rub-impact model
Authors: MA Hui, TAI Xingyu, LI Hui
PP: 1492-1498
Abstract: This paper used the single span double plate rotor system as the research object, based on the Hertz contact theory, established a node to the stator rubbing model, and adopted Newmark-β numerical algorithm to study the influence of speed and amount of unbalance dynamic characteristics of the system. The results of the study showed that, with the increase of rotating speed, the system movement changed from period 1 through period 2 and 3 turn to period 4. The amplitude obviously increased with amount of unbalance. The results provided a basis for the optimization design of the rotating machinery and the rotating machinery happened in the dynamic behaviors of rubbing.
Keywords: mechanical dynamics and vibration; Hertz contact theory; single point rubbing; amount of unbalance; Newmark-β numerical integration