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Frontiers of Chemical Science and Engineering 2015年第3期9卷 259-261页

作者： Yuan, Yingjin Li, Zhenhua tianjin univ Sch Chem Engn & Technol Tianjin 300072 Peoples R China

Founded on October 2 in 1895 as Peiyang university by Mr. Xuanhuai Sheng under emperor Guangxu＇s authorization, Qing Dynasty, tianjin university （TJU） will celebrate its 120th anniversary on October 2, 2015. Thanks for the guidance and support from Professor Jingkang Wang, Editor-in-Chief of the Frontiers of Chemical Science and Engineering, we are honored to edit this special issue as part of the celebration program.

关键词： engineering tianjin university special issue

EFFECTS OF MASS TRANSFER ON THE THINNING AND RUPTURE OF A PLANE PARALLEL LIQUID FILM

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Chinese Journal of Chemical Engineering 1994年第3期2卷 33-49页

作者：李佟茗 tianjin univ Tianjin China

The effects of mass transfer and physical properties upon the thinning and rupture of adraining plane parallel film are *** equation is derived in which the thinning rate is afunction of bulk *** properties(surface tension,surface viscosities,and the variationof surface tension with surface concentration),intermolecular forces(London-van der Waals forcesand electrostatic double layer forces),adsorption and surface diffusion coefficients,bubble size andfilm *** estimation for the critical thickness at which a film rupture is carried out and thecoalescence time is obtained by integration to the critical thickness,The coalescence time is predictedas a function of bulk and surface properties,London-van der forces,adsorption and surfacediffusion coefficients,and bubble size.

关键词： bubble coalescence thin film drainage mass transfer effect on coalescence

ASSESSING THE DYNAMIC ERRORS OF COORDINATE MEASURING MACHINES

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Chinese Journal of Mechanical Engineering 1998年第4期11卷 58-64页

作者： Dong, Chensong Zhang, Guoxiong Mu, Yuhai tianjin univ Tianjin China

The main factors affecting the dynamic errors of coordinate measuring machines are analyzed. It is pointed out that there are two main contributors to the dynamic errors: One is the rotation of the elements around the joints connected with air bearings and the other is the bending of the elements caused by the dynamic inertial forces. A method for obtaining the displacement errors at the probe position from dynamic rotational errors is presented. The dynamic rotational errors are measured with inductive position sensors and a laser interferometer. The theoretical and experimental results both show that during the process of fast probing, due to the dynamic inertial forces, there are not only large rotation of the elements around the joints connected with air bearings but also large bending of the weak elements themselves.

关键词： Coordinate measuring machine Dynamic error Laser interferometer Inductive position sensor

SECONDARY　INSTABILITY　WITH　RESPECT　TO　SPATIAL　GROWING　THREE－DIMENSIONAL　SUBHARMONIC　DISTURBANCES　IN　BOUNDARY　LAYER　FLOW　WITH　SUCTION

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Journal of Hydrodynamics 1995年第3期7卷 7-12页

作者： Zhao, Gengfu tianjin univ Tianjin China

In the paper secondary instability theory is used to analyse the effect of suctions on the characteristics of spatially growing 3-D subharmonic disturbances in boundary layer flow. The end results indicate that increasing suctions can delay the onset of primary and secondary instability, decrease the amplification factors, shows an apparent laminar flow control on the boundary layer flows. The secondary instability of 3D subharmonic disturbances occurs only if the amplitude of TS wave exceeds the threshold value.

关键词： boundary layer suction secondary instability

SIMILITUDE ANALYSIS AND SIMPLIFIED MODELS FOR WATER WAVES INDUCED BY EXPLOSION

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Journal of Hydrodynamics 1991年第3期3卷 41-49页

作者： Guo-guang, Shen De-jun, Li Xin, Lin Jing-chang, Yang tianjin univ Tianjin China

The similitude analysis of water waves induced by an explosion are investigated based on the principle of dimensional analysis in this paper. From the mechanism of water waves generated by an explosion, two mechanical models, formation of an initial crater and evolution of a water-column are proposed. The numerical simulation is accomplished by using the MAC method. The results indicate the importance of determining an equivalent water column for the prediction of some essential wave factors. Compared with the 8 kg TNT explosion touching water surface, the size of equivalent water column is obtained.

关键词： Computers Applications Fluid Mechanics Hydrodynamics

VELOCITY DISTRIBUTIONS OF SUSPENDED SEDIMENT-LADEN FLOWS IN OPEN CHANNELS

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Journal of Hydrodynamics 1997年第4期9卷 37-45页

作者： Cao, Zhixian Xi, Hezhong Zhang, Xiaoxian tianjin univ Tianjin China

Analysis on velocity distributions of steady, uniform suspended sediment-laden flow in open channels was presented. The sediment particle-particle interactions and the buoyancy effects due to density stratification were taken into account through a water sediment mixture's constitute relationship and an adapted Monin-Obukhov length scale to validate the theory for a wider spectrum of sediment concentrations. The developed model with the same Von Karman coefficient as that of a single phase flow was shown to be in the excellent agreement with the measurement results in the controlled experiments with both the low and heavy sediment concentrations.

关键词： Fluid dynamics Open channel flow Sediment transport Sediments Suspensions (fluids) Velocity measurement

PROPAGATION AND BREAKING OF WAVES ON SLOPING BEACH

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Journal of Hydrodynamics 1993年第1期5卷 1-9页

作者： Chen, Miaofu Zhao, Yaonan tianjin univ Tianjin China

In this paper the propagation and breaking of the solitary wave,the sinusoidal wave and the second Stokes wave on a slope of 1/30 are discussed based upon the TUMMAC method,and the velocity fields of breaking waves on the slope are obtained by using the tracing *** results for wave deformation are in good agreement with experimental data,and the breaker indexes depending on the kinetic criterion agree approximately with previ- ous ***,compared with the experimental results measured by Iwagaki and by the authors,the tendency of velocity distribution of breaking waves computed by this numerical method is also satisfactory.

关键词： MAC method breaking wave sloping beach wave deformation

Genetic Algorithms for Auto-Clustering in KDD

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Journal of Systems Engineering and Electronics 2000年第3期11卷 53-58页

作者： Li, Minqiang Li, Jianwu Kou, Jisong tianjin univ Tianjin China

In solving the clustering problem in the context of knowledge discovery in databases (KDD), the traditional methods, for example, the K-means algorithm and its variants, usually require the users to provide the number of clusters in advance based on the pro-information. Unfortunately, the number of clusters in general is unknown to the users who are usually short of pro-information. Therefore, the clustering calculation becomes a tedious trial-and-error work, and the result is often not global optimal especially when the number of clusters is large. In this paper, a new dynamic clustering method based on genetic algorithms (GA) is proposed and applied for auto-clustering of data entities in large databases. The algorithm can automatically cluster the data according to their similarities and find the exact number of clusters. Experiment results indicate that the method is of global optimization by dynamically clustering logic.

关键词： Data reduction Database systems Error analysis Optimization

INTERACTION BETWEEN WAVES,STRUCTURES AND SAND BEDS

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Journal of Hydrodynamics 1995年第4期7卷 103-110页

作者： Gao, Xueping Zhao, Zidan tianjin univ Tianjin China

This dissertation includes two parts. In part one, the standing wave motions and scours of sand bed in front of breakwaters by waves were investigated systematically. The wave surfaces and velocity field with an arbitrary bottom boundary were calculated based on the MAC method (Marker and Cell method). The scours in front of breakwaters under the action of standing waves, breaking waves and broken waves were investigated systematically based on experiments and theoretical analysis. Meanwhile, the sediment threshold was studied. In part two, a new concept consolidation force for the properties of consolidated silt was suggested in order to study the threshold and transportation, then, the erosions around an artificial island built on consolidated silt sea bed under the action of combined waves and currents were investigated by the Physical Model based on the principle of the Series Model method.

关键词： Breakwaters Consolidation Flow interactions Numerical analysis Sand Sediment transport Water waves

SIMPLIFIED MODEL AND ITS APPLICATION FOR WAVEMAKING INDUCED BY EXPLOSION

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Journal of Hydrodynamics 1995年第1期7卷 33-44页

作者： Shen, Guoguang Li, Dejun tianjin univ Tianjin China

This paper pays attention to the analysis of overall macroscopic process of wavemaking induced by explosion. Based on establishing the simplified model and MAC method, the numerical simulations for formulating crater induced by touching water surface explosion, the bubble jumping out of the water surface induced by underwater explosion as well as hollow column formation for large equivalent explosion etc were carried out. In order to predict the wave field, the scheme simulated by falling and evoluting of an ″equivalent cylinder″ were proposed. In addition to researching the wavemaking response in a harbour, two joining methods in time domain were presented. The results indicate that the model and numerical methods are feasible.

关键词： Bubbles (in fluids) Computer simulation Explosion testing Mathematical models Surface waves