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2005 Vol. 31, No. 02

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Attitude control based on inverse dynamics and online parameter identification
Liu Jiarun, Shen Gongzhang
2005, 31(02): 111-115.
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Traditional integrated flight/fire control system uses a proportion-integral-differential(PID) structured flight/fire coupler, which results in lack of robustness and huge design workload. A synthesis method based on inverse dynamics and online parameter identification was developed and was directly used to design the attitude controller in the integrated control system. The inverse dynamics in analytical form was obtained by deducting the dynamic equation of aircraft rotation. The aerodynamic parameters wear estimated through online parameter identification method and were used for actuator deflect allocation. Digital simulation using a six degree-of-freedom nonlinear aircraft model was conducted, which demonstrates rapid response, good decouple performance among axes, and good robustness with respect to aerodynamic model error. The proposed method can be also applied to general aircraft attitude controller design.
Experimental investigation on temperature oscillation of loop heat pipes
Zhang Hongxing, Lin Guiping, Ding Ting, Shao Xingguo
2005, 31(02): 116-120.
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The phenomenon of temperature oscillation in loop heat pipes was described and explained. Test results indicate that temperature oscillation frequently occurred at very low and very high heat loads. At low start-up heat loads evaporation inside the primary wick was easy to occur when the evaporator, including vapor grooves and evaporator core, were flooded with liquid. Evaporation inside the wick will lead to the temperature oscillation at the condenser inlet. Start-ups with temperature oscillation at the condenser inlet will shift the steady state operating temperatures higher than normal. While at high heat loads, vapor can not be condensed absolutely in condenser for its limit ability to reject heat and temperature oscillation will occur at the condenser outlet, which can be avoided by increasing the working fluid charge mass.
Stability on the damping capacity and microstructure of the high strength damping aluminum alloy
Ma Yue, Zhao Haitao, Han Haijun, Xu Huibin, Li Peiyong, Li Wei
2005, 31(02): 121-124.
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The stability on the damping capacity and microstructure of the X7093/5(Zn-30Al) high strength aluminum alloy prepared by rapid solidification and powder metallurgy process was investigated with aging treatment. The alloy was aged at 50℃,100℃,120℃ for 10 h,50 h,100 h separately and then air cooled. The damping capacity and microstructure variation was tested with dynamic mechanical thermal analysis(DMTA) and transmission electron microscope(TEM). The result shows that the microstructure of the alloy changed from fine crystals to large crystals with regular and sharp grain boundaries, the effect of grain boundaries on the damping capacity increased. From room temperature to 250℃, the damping capacity increased from 4×10-3 to 3.0×10-2. Aging time and temperature do not have significant effect on the damping capacity below 120℃ and 100 h and the alloy kept excellent stability.
Fault-tolerance dual computer system based on maintainability without powering off
He Yuzhu, Dong Junwei, Luo Yong, Li Xiao
2005, 31(02): 125-127.
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To improve the reliability of controller of a microcomputer, a fault-tolerant system which is consisted of two ones was proposed. In this system, output of a microcomputer was transmitted into another microcomputer through the serial ports, it was compared with the pre-stored data to carry out the diagnosis each other. The address encode technique was employed to implement the automatic switchover between two microcomputers and to insulate the fault unit diagnosed. After the fault unit was repaired and returned to the system(plug and play an electronic unit on-line), it waited through testing the task number of system program until the first command of next task was detached for synchronous. Experiment result shows that the controller can detect the fault in real time, and the failure device can be displaced without powering off.
Implementation and evaluation of measurement tool for Java
Li Nuo, Jin Maozhong, Liu Chao
2005, 31(02): 128-133.
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Introduce object-oriented metrics; define the detailed definitions of McCabe, Halstead and weighted methods per class(WMC) for Java; a new method for implementation of measurement tool for Java was offered; demonstration for using this tool to optimize program and enhance software quality was also given. Experiments show that this tool helps programmers to improve program effectively. They also show that the module with high measurement value are inclined to be complex, fallible, hard to maintain and need consume amount of labor, so testers have to pay more attention to test those modules. Developers must re-exam those modules, check their logic, and try to optimize them to depress their measurement value. By providing adequate experiment data, The results show that software measurement plays an essential roll for improving software quality. The metrics used are depth of inheritance tree(DIT), number of children(NOC), McCabe, Halstead, weighted methods per class(WMC) and response for a class(RFC). They help programmers analyze Java program at three aspects——the inheritance metrics, the module complexity metrics, and the communication metrics. So each kind of the metrics measures Java program from different aspects, evaluates the software quality effectively, and reveals the probable bugs.
Stretch bending of aluminum extrusion
Diao Keshan, Zhou Xianbin, Li Xiaoxing, Jin Chaohai
2005, 31(02): 134-137.
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An experimental study on stretch bending of aluminum extrusion was conducted under different pre- and post-stretching elongation. Cross section distortion caused by radial stress during bending process is one of main parameters concerning forming precision. As shown in the test, cross section distorted as the extrusion was bent into contact with the die. Main distortion of cross section is sagging of upper flange. Sagging distribution along the extrusion was given and sagging of middle cross section is not the maximum. It can be seen that the larger is pre- or post-stretching elongation, the larger is cross section distortion. Springback is a common phenomenon during the unloading process, which is influenced by many parameters and difficulty to be eliminated. Pre-and post-stretching elongation can both reduce springback. When pre-stretching elongation exceeds a certain value, its effect on reducing springback is not obvious, which is similar with post-stretching elongation.
Calculation of lid-driven cavity flow using GAO-YONG turbulence equations
Ren Xin, Gao Ge
2005, 31(02): 138-141.
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A two-dimensional stationary incompressible lid-driven cavity flow was numerically simulated employing staggered grid arrangement, incompressible SIMPLER method and QUICK scheme to solve GAO-YONG turbulence equations. The vorticity contour in the cavity and the velocity changing curve of cavity's central horizontal section line were acquired and compared with directly numerical simulation(DNS) result qualitatively and the consistency was very good. It shows that the mechanical energy equation corresponding to the scales of nonlinearity in the turbulence equations is very important for the turbulence equations to reasonably simulate the complex distribution of eddy viscosity coefficients and the inversion phenomenon of turbulence energy in the lid-driven cavity flow. Farther the GAO-YONG turbulence equations being able to gain real viscosity field in complex flow was proved.
Implementation of Chirp Scaling algorithm based on space-borne real-time SAR processor
Zhou Yinqing, He Min, Chen Jie, Li Chunsheng
2005, 31(02): 142-147.
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Based on the refined Chirp Scaling image formation algorithm, an efficient method for real-time processor on space-borne synthetic aperture radar (SAR) was presented. Its key technique is applicable to other precise imaging algorithms for high resolution space-borne SAR. The configuration of the real-time processor was introduced, the granularity of the data being processed and its parallel pipeline structure were analyzed. The processing flow for a single granularity was redesigned, and the efficient implementation method was discussed. Experiments were performed upon the real-time processor using simulated SAR echo data. The whole progress was completed in 41 seconds. The conclusion is that the implementation method is validated by the processing speed and image quality, which meet the requirement of the system.
Two significant technique requirements in supersonic airliner design
Jiang Chongwen, Huang Jun, Cao Yihua
2005, 31(02): 148-152.
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Supersonic airliner (SSA) is a significant development orientation for the future commercial transport. Two significant technique requirements, based on the study of the payload, range and velocity of new supersonic airliner, was deduced for SSA design. At first, a fuselage arrangement technique applicable to SSA was derived from imitating subsonic airliner fuselage arrangement method in a creative way. The demand of the passenger total to fuselage arrangement was indicated. A sample analysis shows that this technique is reasonable and available in engineering. Secondly, transforming the Breguet range equation with several relative assumptions and using weight estimate gains the relation between the takeoff weight, fuel used in mission and lift-drag radio in cruise. The requirement of SSA operating economics to the lift-drag radio in cruise was obtained. The gained two requirements have significant roles and directional value in multidisciplinary optimization design of SSA.
Transducer of the ultrasonic elliptical vibration cutting based on the finite element method
Li Xun, Ji Yuan, Zhang Deyuan
2005, 31(02): 153-156.
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An asymmetrical structural model of the ultrasonic elliptical vibration transducer only with the longitudinal animation was presented through analyzing the model of the longitudinal vibration transducer. Based on the modal and static analysis of the finite element method, the various parameters of the model were modified to meet the needs of the vibration modality and the inherent frequency. A system of the ultrasonic elliptical vibration cutting with the single longitudinal animation was developed. The surface finish with high quality can be achieved by the ultrasonic elliptical vibration cutting with a polycrystalline diamond (PCD) tool. It is proved that the ultrasonic elliptical vibration transducer can be rational designed with the finite element methods in respects of parameter optimization and modal analysis. At the same time, the ultrasonic elliptical vibration cutting can improve the quality of the surface finish effectively.
Training sequence based carrier frequency synchronization method for OFDM system
Yang Chenyang, Hong Huiyong
2005, 31(02): 157-161.
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Based on the study of single estimation of phase-offset induced by frequency offset, two independent phase-offset estimations which could expand the capture range of frequency offset was thoroughly analyzed, and a trainingsequence based carrier frequency synchronization method for orthogonal frequency division multiplexing(OFDM) system was proposed. The method take the advantage of two independent phase-offset estimations to remove the potential phase ambiguity existed in a phase-offset estimation, soas to recover the carrier frequency in a wide range. Theoretical analysis and simulation tests were provided to evaluate the performance of the method. Since the frequency offset is estimated in time domain, this method is easier to implement with much less complexity comparing with other wide range carrier frequency recovery methods.
Path tracking control and simulation of underwater vehicle
Xu Liang, Bian Yushu, Zong Guanghua
2005, 31(02): 162-166.
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Path tracking of underwater vehicle was discussed. The kinetic equations of 6-degree of freedom underwater vehicles were given first, taking into account the gravity, buoyancy, thrust power and ocean current etc. Then a nonlinear controller, which includes an inner loop and an outer loop, was designed to track the geometric path. In inner loop, nonlinear compensation was imported to simplify the robot system to a linear system, in outer loop, negative feedback was used to correct the wrap between the actual path and ideal path. Simulation results about pursuing surface vehicles and tracking helical line were given to demonstrate the proposed scheme. Simulation results show that the strategy has nice performance of tracking ability.
Structure evolution of the steady and symmetric vortex pattern around a slender
Li Guohui, Deng Xueying, Ma Yu
2005, 31(02): 167-171.
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The structure evolution of flow pattern around a slender was calculated by numerical method. It was pointed that the development of slender vortices leads to the change of topological structure about cross flow, and a critical flow pattern will appear. A high-order singular point in this flowfield was analysed by differential equation qualitative theory. The index of the high-order singular is -3/2. The topological structure of this singular point is instable, so bifurcation will be occurred and the topological structure of flowfield will be changed by little disturbance. The 3-dimensional flow structure of the steady and symmetric vortices pattern around a slender was gained.
Adaptive feedback control method for active vibration isolation based on on-line frequencies estimation
Zhang Lei, Liu Yongguang, Fu Yongling, He Lin
2005, 31(02): 172-176.
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As the adaptive feedforward control method used for active control of periodic vibration has many shortcomings, an adaptive feedback control method was proposed based on on-line frequency estimation. The vibration disturbance was recovered with the error signal, and the frequencies of periodic components in disturbance were estimated using cascaded adaptive notch filters, whose parameters were adjusted with recursive least mean algorithm(RLS). Reference signals were produced at the estimated frequencies as controller inputs, and controller weights were adjusted based on Lyapunov stability theory. Simulation and experimental results show the frequency estimation method has good estimation accuracy, the adaptive feedback control method can gain over 16 dB vibration isolation at the vibration frequency, and the controller parameters adjustment is fast.
Aerodynamic configuration of hypersonic vehicle based on waverider body design
Zhang Dongjun, Wang Yankui, Deng Xueying
2005, 31(02): 177-181.
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The waverider with high lift-drag ratio was designed by the inverse-design method based on inviscid conical shock wave. When the basic conical shock wave is 12°, an effective improvement of the lift-drag ratio was obtained for the effect of the decrease of the pressure on the upper surface of the waverider. As the result of the figuration optimization, the value of lift-drag ratio increased to 4.598 1 from 3.356 3 taking account of the viscous effect at Mach 6. An hypersonic configuration of the single-stage-to-orbit(SSTO) adopting the waverider with high lift and low drag as the body was designed. Through the way of numerical simulation, the primary result shows that this configuration with static stability has a satisfying value of L-D ratio.
Construction of coherent 3D geological blocks from stratified geological structure
Meng Xianhai, Yang Qin, Li Jigang
2005, 31(02): 182-186.
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Building geometry model of complicated geological entity is important work in exploration and exploitation oil and gas field. With the introduction of geological geometry modeling method, the trend of syncretizing the surface modeling and solid modeling was pointed out, and an integral modeling method based on the TIN model was presented. Data structure of geological block was presented based on improving on half-edge data structure, and the algorithm of constructing coherent 3D geological blocks from completed stratified geological structure and some results was presented. The algorithm is very useful for building the solid model of geological structure and also can be used in several actual projects of forward modeling, ray tracing method and visualization of 3D geological model.
Numerical analysis for underground concrete oil tank
Huang Dahai, You Xusheng
2005, 31(02): 187-191.
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A new vessel,the prestressed concrete (PRC) oil tank,for the strategic petroleum reserve(SPR) was represented. With the application of structure analysis software ANSYS, the distribution of the temperature and stress in the side wall of the oil tank was given,in which the stress is caused by the temperature,and the temperature and temperature stress changes with the time,and the maximum temperature stress happens at the top of the side wall at the early time of the oil storage. When filling the heat insulation layer in the side wall of the oil tank,the loop stress in the inner side wall reduces,and the stress in the outer wall increases. So in the design practice the joint of the inner and outer wall should be designed specially to satisfy the displacement caused by the temperature.
Automatic focusing system of micro-vision based on image analysis
Sun Minglei, Zong Guanghua, Yu Zhiwei, Bi Shusheng, Yu Jingjun
2005, 31(02): 192-196.
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An automatic focusing system of micro-vision for micro alignment assembly was developed. The system was based on spatial domain analysis. First-order differential operator in y direction was choosed as focusing evaluation function to realize autofocus quickly and accurately. Processing the image in a choosed focusing window was presented to optimize focusing effect. A new focusing algorithm was put forward, which is different from hill climbing searching algorithm(HCSA). The key factor of the algorithm is establishing the relation between defocus values and focusing evaluation. Cubic spline interpolation was adopted to establish focusing relation function to realize the algorithm effectively. It proves the system can realize autofocus accurately and quickly.
Remote sensing image compression based on visual model and image feature
Jiao Runhai, Li Yuancheng, Hou Jingbiao
2005, 31(02): 197-201.
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With characteristics of complicated texture and rich edges, remote sensing image is usually hard to achieve high compression ratio. Energy distribution among wavelet subbands at different orientations and scales was statisticed, then an adaptive quantization method for different wavelet subbands coefficients was proposed, in the method contrast sensitivity function(CSF) of human vision system(HVS) and energy distribution characteristic were both considered. The quantization method was applied to an existing embedded wavelet image coder and the compression results show that comparing with method without psychovisual quantization, this method gets better visual quality under the same compression ratio (only with little peak signal noise ratio(PSNR) degradation).
Heat transfer in complex passages of turbine blade trailing edge
Li Li, Ding Shuiting, Tao Zhi, Xu Guoqiang, Zhao Shihong
2005, 31(02): 202-205.
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An experimental comparison research of endwall heat transfer characteristics was conducted in the complex passages of turbine blade trailing edge by using thermochromic liquid crystal method. Three kinds of diaphragm plates between two passages were studied to obtain optimal heat transfer effect. Results indicate that the radial inflow cooling air in first passage passes through the orifices in the diaphragm plates ceaselessly then changes to spanwise cooling air, which impinges the second passage and flows away through the orifices along the trailing edge can enhance heat transfer of the trailing edge; uniform configuration of orifices in diaphragm plate provides better heat transfer effect than that of others.
Numerical simulation of the 3-D unsteady flow in the last stage of the steam turbine
Qi Lei, Zheng Ning, Cheng Honggui
2005, 31(02): 206-211.
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Air cooling steam turbine uses air as working fluid, and it works in variable-operating condition. It is important for the design of air cooling steam turbine and the performance and stability of turbine to study unsteady flow mechanism in design and off-design state. The flow of turbine in design and off-design state was simulated by the method of numerical simulation of 3-D viscous flow, and the flow mechanism in design and off-design state was studed. The results show rotor-stator interaction causes unsteady flow in design state, and the rotor-stator interaction in off-design state is weak, the unsteady phenomena is not obvious in off-design state.
Optical pulse active replicator based on fiber-optic delay-time
Feng Da, Li Zheng, Zheng Zheng, Chen Yuxiao, Tang Dan
2005, 31(02): 212-217.
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Based on the fiber circulating delay line, an optical pulse active replicator using semiconductor optical amplifier (SOA) was proposed for high-fidelity replication of short analog optical pulses according to the requirements of a short optical pulses measurement system. Taking into account amplified spontaneous emission (ASE), a numerical model of SOA was developed in order to investigate a single-shot optical pulse recirculating propagation in the active replicator with a SOA. Simulation and analyses indicate that the optical pulse active replicator, which uses pumping light injection to restrain pulseshape distortion, is feasible. The number results provided optimal design bases for the optical pulse active replicator by choosing appropriately operating parameters, such as the power of pumping light injection and the loss within the replicator loop.
Modeling of airliner gasoline tank and modification of attitude error of sensor
Jin Yulin, Zhuang Daming, Yang Qin
2005, 31(02): 218-222.
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The algorithm of modeling civil airliner gasoline tanks and modifying the attitude error of tank volume sensors was provided. Tank surface was generated with triangle mesh based on two-dimensional Delaunay triangulation and interpolation. Using the wrong result of gasoline volume sensors, current attitude error and surface triangle mesh, logical prisms and tetrahedrons were generated. The correct volume was calculated with total volume of prisms and tetrahedrons. The algorithm was compared with the current slice algorithm in efficiency and applicability. Solving the three-dimensional modeling of civil airliner tank and the modification of attitude error of tank volume sensors with that finished model, this algorithm is more effective and efficient than slice algorithm.
New definition method of state of charge for batteries in HEV
Wu Hongjie, Qi Bojin, Zheng Minxin, Chen Bo, Shu Weihui
2005, 31(02): 223-226.
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A new definition method to describe the state of the batteries in a hybrid-electric-vehicle (HEV) was proposed. The batteries in the question are MH/Ni batteries which have a normal capacity of about 8 A·h, and were used in a kind of HEV. The HEV application is a very harsh environment with high charge or discharge rates and very dynamic rate profiles. The normal definition method state of charge (SOC) that worked well in benign portable electronic applications may not work well in the HEV application. The normal definition of SOC cannot contain both the static and the dynamic message of the batteries in the only word. In the new definition method, the static state of charge (SSOC) and the dynamic state of charge (DSOC) were proposed. The SSOC indicates the static capacity message of the batteries; the DSOC indicates the dynamic state of charge while charging or discharging. The methods of how to calculate the SSOC and the DSOC were discussed.
Integrative framework for heterogeneous synchronous collaboration systems
Li Lüsong, Li Jing, Yu Min, Yu Jianjun
2005, 31(02): 227-231.
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To solve the communication problem of synchronous collaboration systems with heterogeneous architectures, the integration of the heterogeneous systems was discussed. A new formalized mode of synchronous collaboration system was proposed and key integration operation was defined, based on the set theory. While analyzing the integration, the agent mechanism was used to avoid the differences of resources and networks between heterogeneous collaboration systems and the multicast transport mechanism was used to link the several collaboration systems at a session. The integrative framework with four levels was developed, based on the two mechanisms. The prototype system according to the integrative framework was developed, based on web-services technology. The system realized the integration of three kinds of collaboration systems including H.323 set of standards based collaboration systems, Session initiation protocol(SIP) based collaboration systems and IP-multicast based collaboration systems. The users of the heterogeneous collaboration systems can communicate with each other.
Application of virtual instrument based on CAN bus in multi-motor control system
Huang Jian, Han Mei
2005, 31(02): 232-235.
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The concept of virtual instruments was applied in a multi-motor control system to monitor each motor’s movement track and character of current, in order to realize optimal control. The multi-motor control system adopted client/server structure based on controller area network (CAN) bus, and the virtual instrument became the host unit replacing the motor control center in the development phase to debug and measure each motor control client unit. The visual instrument was built using CAN card and visual basic. It could adjust proportional-integral differential(PID) parameters of motors controller online, show the result digitally and graphically, update the digital signal processor (DSP) and field programmable gate array (FPGA) program on board and emulate some testing environment, and dramatically improve the development efficiency and product quality of certain type of X-ray machine.
Optical, electrical and infrared emissing properties of DC magnetron sputtered ZnO:Al thin films
Wang Wenwen, Diao Xungang, Wang Zheng, Wang Tia
2005, 31(02): 236-241.
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Aluminium-doped zinc oxide (ZnO:Al) films were deposited on glass substrate by DC reactive magnetron sputtering from a Zn-Al metallic target (ω(Al)=3%). Films with novel, tangly string-like surface morphology, an average optical transmittance up to 90% in the visible range, a widest band gap of 3.47 eV and electrical resistivity down to 1.80×10-6 Ω·m were obtained. The infrared emissivity in 8~14 μm waveband is distributed in the range of 0.26~0.9. The surface morphology, crystallinity, infrared emissivity as well as the electrical and optical properties of the samples were characterized using X-ray diffraction, scanning electron microscopy, spectrophotometry, infrared radiometer and Hall-effect measurement. The optical, electrical and infrared emissing properties of the films depend on substrate temperature and sputtering power obviously and regularly. The relationship between sheet resistance and infrared emissivity of ZnO:Al(ZAO) thin films follows a quadratic function as the sheet resistance is below 45 Ω.
On-site induction brazing of tubes
Zhang Wei, Qi Bojin, Jin Yulan, Zhang Jin
2005, 31(02): 242-246.
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In a plane factory, some tubes connection is in the plane by welding. Traditional induction brazing device with a fixed coil could not adapt this new process. Considering the characteristic of on-site induction brazing of tubes, a set of equipment and related technologies were developed, including a special low loss connecting power cable,a precise measurement and control system of brazing temperature with a fiber,and an ultrasonic induction heating inverter, and necessary experiments were done. The results show that this device and related technologies can satisfy the welding quality and is successfully applied in the factory.
Stacking sequence optimization of composite laminate applying genetic algorithm of immunity
Lu Dawei, Li Shu
2005, 31(02): 247-250.
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The sequence of composite laminate was optimized by genetic algorithm (GA) of immunity. The immunity mechanism was used to improve the convergence efficiency and solve the precocity problem of GA. The mathematic model was built to optimize the inplane geometry and bend factors. The optimization result was searched by cross and mutation and other genetic operations. The acceleration and restrain mechanism of immunity system was used to adjust the diversity of individuals. The stacking sequence of composite laminate was calculated at given inplane geometry and bend factors. The numerical results show the superiority and practicability of GA of immunity comparing with the results of standard GA.
Ab initio calculations of anatase TiO2
Cao Honghong, Huang Haibo, Chen Qiang
2005, 31(02): 251-254.
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When photoelectrochemical cell possessing an anode of TiO2 was reported, photocatalysis has developed into a major area of intensive investigation. The results of the self-consistent calculations on the anatase phase of TiO2 was presented. The calculations were performed using the full potential-linearized augmented plane wave method (FPLAPW) in the framework of the density functional theory (DFT). The fully optimized structure, obtained by minimizing the total energy and atomic forces, is in good agreement with experiment. Electronic structures were calculated such as band structure and X-ray spectra,etc.
Finite element analysis of O-ring seal structure
Hu Dianyin, Wang Rongqiao, Ren Quanbin, Hong Jie
2005, 31(02): 255-260.
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Applying the theory of nonlinear finite element analysis, the stresses and strain of the elastomeric O-ring seals at storage and working process were analyzed. The factors influencing sealing performance were considered, such as gap between upper and nether flange, initial compressibility, groove width, sealing materials, O-ring section diameter and the work temperature. Results show that the gap breadth, initial compressibility and seals material do great contributions to the maximum contact normal stress, and the groove notch and bottom fillets act upon the maximum shear stress obviously. The analysis lays the foundation of the optimum design of sealing structure. Based on the stresses distribution and the brittle position, the failure mode & criteria were discussed and established.
Fluid flow and heat transfer characteristics in the leading of blades at rotating state
Zhu Jinrong, Wu Hong, Tao Zhi, Ding Shuiting, Xu Guo
2005, 31(02): 261-264.
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Numerical simulation was performed to study the cooling configuration in the leading of blades at rotating state. The configuration was consisted of entering gas cavity, trailing edge and leading edge blocks. Computation was carried out for the different rotating velocity. The influence of rotating velocity on the fluid flow and heat transfer characteristics of this configuration was carried out. To impinging flow along the blade with outflow film under rotating state,the conclusion of numerical computation is given as follows:The heat transfer of the leading and trailing impingement surfaces are enhanced with the rotating velocity increasing. The heat transfer at the blade trailing impingement surface is stronger than at the leading impingement surface. The difference of heat transfer between the leading and trailing impingement surfaces decreases with the rotating velocity increasing.

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