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Parameter Identification of Hydraulic Low Pressure Pipeline Transient Model Using Parallel Genetic Algorithms

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Parameter Identification of Hydraulic Low Pressure Pipeline ...

Virtual multi-dimensional internal bonds model and its application in simulation of rock mass

第五届流体传动与控制国际会议

作者： Yang Chifu~* Li Songjing Jiang Dan department of Fluid Control and Automation harbin institute of technology harbin Heilongjiang {3. china

＜正＞Parameter identification of pressure transient models accompanying cavitation and gas bubbles inside low hydraulic pipelines using parallel genetic algorithms（PGA）in a cluster of computers is presented. In this paper,pressure transient models are given to describe the flow behavior in a pipeline,and the numerical models of cavitation and gas bubbles are built to calculate the cavitation volume and gas bubble volume during the *** unknown parameters of the pressure transient mathematical models include the initial gas bubble volume,gas resolving time and gas releasing time *** identification of pressure transient mathematical models with genetic algorithms（GA）on a single computer usually takes seven or eight days,which is out of *** execution time of GA becomes high due to time consuming of evaluating fitness *** order to predict the pressure transients and shorten the execution time of GA,MATLAB Distributed Computing toolbox and MATLAB Genetic Algorithms toolbox are used to perform evaluation of fitness function at each generation by PGA,which is a parallel calculation on a cluster of *** on the minimization of the least-square errors between experimental data and simulation results,PGA is applied to search for global optimal model *** rate of computation time using PGA to using GA is acquired. Simulation results with identified parameters obtained by PGA are *** of simulation results with experimental data indicates that PGA is feasible to estimate unknown parameters in hydraulic low pressure pipeline transient model.

关键词： parallel genetic algorithms parameter identification pressure transients

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Science china(Technological Sciences) 2008年第2期51卷 192-201页

作者： ZHANG ZhenNan1,2 & GE XiuRun3.4 1 department of Civil Engineering,Shanghai University,Shanghai 200072,china 2 Shanghai institute of Applied Mathematics and {3.,Shanghai University,Shanghai 200072, china 3.institute of Geotechnical Engineering,Shanghai Jiao Tong University,Shanghai 20003.,china 4 institute of Rock and Soil {3.,Chinese Academy of Sciences,Wuhan 43.071,china department of Civil Engineering Shanghai University Shanghai institute of Applied Mathematics and mechanics Shanghai University institute of Geotechnical Engineering Shanghai Jiao Tong University

VMIB (virtual multi-dimensional internal bonds) is a multiscale mechanical model developed from the VIB (virtual internal bond) theory. In VIB theory,the solid mate-rial is considered to consist of random-distributed material particles in microscale. These particles are connected with normal bonds. The macro constitutive relation is derived from the cohesive law between particles. However,in VMIB,the micro particles are connected with both normal and shear bonds. The macro constitutive relation is derived in terms of bond stiffness coefficients. It has been theoretically certified that there exists a corresponding relationship between the two bond stiffness coefficients and the two macro material constants,i.e. the Young’s modulus and Poisson ratio. This corresponding relationship suggests that it should be necessary and sufficient to simultaneously account for the normal and shear interactions between particles. Due to the fact that the fracture criterion is directly incorporated into the constitutive relation,both VIB and VMIB present many advantages in simulating fractures of materials. In the damage model of rock mass,a damage tensor is usually defined to describe the distribution of cracks. The damage value in one direction determines the relative stiffness of rock mass in this direction. In VMIB solid,the relative distribution density of micro bonds in one direction determines the relative macro stiffness of the material in this direction. The effects of the damage value and the relative distribution density of bonds are consistent. To simulate the failure behavior of rock mass with VMIB,the presented paper sets up a quantitative relationship between the damage tensor and the rela-tive distribution density of bonds. Comparison of the theoretical and the experi-mental results shows that VMIB model can represent the effect of distributed cracks on rock mass with this relationship. The presented work provides a founda-tion for further simulating fracture behavior

关键词： VMIB (virtual multi-dimensional internal bonds) rock mass VIB (virtual internal bonds) multi-cracked body numerical simulation

Corrosion behaviors and formation mechanism of chromate passive film on electroless Ni-P coating

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Corrosion behaviors and formation mechanism of chromate pass...

Numerical Simulation and Experiment of Cavity Growth During Superplastic Bulging of Magnesium Alloy ZK60

2009年全国电子电镀及表面处理学术交流会

作者： Songlin Mu,Ning Li,Deyu Li,Zhongli Zou (department of applied chemistry,harbin institute of technology,harbin {3.)

To develop chromium- free passivation methods for electroless Ni- P coating(ENPC),the passivation mechanism of chromate methods should be researched *** composition and corrosion properties of chromate passive film on ENPC with KCrO 3.g/l as treatment bath,are investigated in this *** morphology of ENPC and passivated ENPC is examined by scanning electronic microscopy(SEM).The corrosion properties of passivated sample are tested by electrochemical *** the chemical composition of the passive film is analyzed with X- ray photoelectron spectroscopy(XPS).SEM result shows that no obvious difference can be observed on surface *** electrochemical impedance spectroscopy(EIS) tests indicate the corrosion current of the treated sample is only 1/3. of that of blank(without treated Ni - P coating).The XPS analysis illustrates that the passive film on ENPC comprises Cr,Ni and *** the thickness of this passive film is evaluated according to sputtering rate of Ar *** analysis by high- resolution XPS spectrum shows a strange result:although the sample is treated by Cr - containing bath,the element Cr in passive film is only in the form of trivalent compounds,no hexavalent chromium can be *** to XPS results,the formation mechanism of conversion coating is discussed and it can be inferred both element Ni and element P play an important role in passivation process.

关键词： Electroless Ni-P coating Passive film XPS Formation mechanism

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Numerical Simulation and Experiment of Cavity Growth During ...

WATER TUNNEL experimental INVESTIGATION ON THE DRAG REDUCTION CHARACTERISTICS OF THE TRAVELING WAVY WALL

The Fourth International Conference on Physical and Numerical Simulation of Materials Processing (ICPNS’2004)

作者： Yandong YU, Kaifeng ZHANG, Hairong ZHENG and Daming JIANG department of Materials Engineering, harbin institute of technology, harbin, {3., P.R.china

In this paper, numerical simulation and experimental studies on cavity growth were carried out during the bulging process of superplastic magnesium Alloy. A three-dimensional rigid-viscoplastic finite element program has been developed and applied to predict the cavity radiusand volume fraction of cavity growth. The final prediction on the cavity radius and volume fraction distribution was exhibited as colorful shade pictures. The experimental studies wereperformed under similar conditions to the numerical one and provided for quantitativecomparison. According to the metallography observation, the radius and volume fraction of cavity growth was quantitative achieved by using Profound-Iron&steel software. The numerical results were in reasonable quantitative agreement with the experiment.

关键词： Magnesium alloy Cavity Numerical simulation Superplastic bulging

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Journal of Hydrodynamics 2011年第1期23卷 65-70页

作者： YAO Yan LU Chuan-jing SI Ting ZHU Kun department of Engineering mechanics Shanghai Jiao Tong University Shanghai 200240 China Beijing Electromechanic Engineering institute Beijing 100074 China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200030 China department of modem mechanics University of Science and Technology of China Hefei 230027 China

Drag reduction experiment of the traveling wavy wall at high Reynolds number is conducted.A suit of traveling wavy wall device is *** drag forces of the traveling wavy wall with various wave speeds（c）are measured under different water speeds（U）in the K15 cavitation water tunnel and are compared with that of the flat *** results show that the mean drag force of the traveling wavy wall have decreased and then increased with oscillation frequency increasing at the same flow *** different flow speeds,when traveling wave wall reached to the minimum of drag force,the corresponding the ratio of the wall motion phase speed c to flow speed U,c /U is slightly *** the parameters of the experiment,whenc /U reaches a certain value,the drag force of the traveling wavy wall can be less than that of the flat *** drag reduction can be up to 42%.Furthermore,as the value ofc /U increases,the traveling wavy wall can restrain the separation and improve the quality of flow field.

关键词： flow control drag reduction traveling wavy wall water tunnel test

experimental INVESTIGATION ON THE DRAG REDUCTION CHARACTERISTICS OF TRAVELING WAVY WALL AT HIGH REYNOLDS NUMBER IN WIND TUNNEL

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Journal of Hydrodynamics 2010年第5期22卷 719-724页

作者： YAO Yan LU Chuan-jing SI Ting ZHU Kun department of Engineering mechanics Shanghai Jiao Tong University Shanghai 200240 China Beijing Electromechanic Engineering institute Beijing 100074 China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Shanghai 200030 China department of Modern mechanics University of Science and Technology of China Hefei 230027 China

Drag reduction experiments of the traveling wavy wall at high Reynolds number, ranging from 1.46×106 to 5.83.106 based on the free-stream velocity and the model length, were conducted. A suit of traveling wavy wall device was developed and its characteristics of drag reduction at high Reynolds number were investigated. The drag forces of the traveling wavy wall with various wave speeds （ c ） were measured at different wind speeds （U ） in the FL-8 low-speed wind tunnel and compared with the drag force of the flat plate. The results show that the mean drag force of the traveling wavy wall decreases as the value of c /U increases, at different wind velocities, the values of c /U corresponding to minimal drag force of the traveling wavy wall are different, when the values of c /U are larger than 0.6, the mean drag forces of the traveling wavy wall are smaller than those of the flat plate, and the drag reduction can be up to 60%. The drag reduction effectiveness of traveling wavy wall is thus achieved. Furthermore, as the value of c /U increases, the traveling wavy wall can restrain the separation and improve the quality of flow field.

关键词： flow control drag reduction traveling wavy wall wind tunnel test

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双振子模型手性分子介质的二次谐波理论

物理学报 2003年第2期52卷 372-376页

作者：郑仰东李俊庆李淳飞哈尔滨工业大学物理系哈尔滨150001

推导了在二次谐波条件下耦合双振子模型手性分子的一阶超极化率 ,给出了薄膜手性介质的二阶极化率 ,分析了分子的微观参量对二次谐波产生效率的影响 .理论计算所得的偏振旋转角谱和已有的实验结果相符 .

关键词：双振子模型手性分子分子极化率介质极化率二次谐波非线性光学

关于加强与推进高校国有资产管理创新发展的探讨

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实验技术与管理 2010年第4期27卷 172-174,178页

作者：何维民哈尔滨工业大学国有资产管理处

结合学校实际和工作实践,就如何加强与推进高校国有资产管理工作,从管理理念、管理方式、管理制度、工作思路到具体工作的效果进行探讨与交流。

关键词：资产管理保值增值效益

β-delayed proton decays near the proton drip line

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Science china(Physics,mechanics & Astronomy) 2005年第3期48卷 257-267页

作者： XU Shuwei 1 , LI Zhankui 1 , XIE Yuanxiang 1 , HUANG Wenxue 1 , SHU Nengchuan 2 , CHEN Yongshou 2 , XU Furong 3., WANG Kun 4 , PAN Qiangyan 1 , WANG Xudong 1 , YU Yong 1 & XING Yebing 1 1. institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 73.000, china 2. Nuclear Physics department, china institute of Atomic Energy, Beijing 102413. china 3. department of Technical Physics, Peking University, Beijing 100871, china 4. Shanghai institute for Nuclear Research, Shanghai 201800, china institute of Modern Physics Chinese Academy of Sciences Lanzhou China Nuclear Physics department China Institute of Atomic Energy Beijing China department of Technical Physics Peking University Beijing China Shanghai institute for Nuclear Research Shanghai China

We briefly reviewed the experimental study on a-delayed proton decays near the proton drip line published by our group during the period of 1996―2004, namely the first observation of the a-delayed proton decays of 9 new nuclides in the rare-earth region and the new measurements of a-delayed proton decays of 5 nuclides in the mass ～90 region near the N = Z line with the aid of the “p-?” coincidence in combination with a He-jet tape transport system. In the meantime some important experimental technique details were supplemented. The experimental results, including the half -lives, spins, parities, deformations and production reaction cross sections for the 14 nuclei were summarized and compared with the current nuclear-model predictions, and then the following points were represented. (1) The experimental half-lives for 85Mo and 92Rh as well as the predicted “waiting point” nuclei 89Ru and 93.d are 5―10 times longer than the theoretical predictions given by M?ller et al. using a macroscopic-microscopic model. It considerably influences the predictions of the abundances of the nuclides produced in the rp-process. (2) The current-model predictions are not consistent with the experimental assignments of the spins and parities for the proton drip-line nuclei 142Ho and 128Pm. However, the nuclear potential energy surface (PES) calculated by using a Woods- Saxon-Strutinsky method reproduced the experimental results. (3. The Alice code overestimated the production reaction cross sections of the studied 9 rare-earth nuclei by one order of magnitude or two, while HIVAP code overestimated them by one order of magnitude approximately.

关键词： proton drip line, β-delayed proton decay, He-jet tape transport system, "p-γ" coincidence, spin, parity, deformation, production reaction cross section.