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中国有色金属学会会刊：英文版 2006年第B2期16卷 439-443页

作者： liu yu GONG Xiao-lu Institut Charles Delaunay CNRS FRE 2848 LASMIS UTT 12 rue Marie Curie BP 2060 10010 Troyes France

Interpenetrating phase composites (IPCs) are a new class of composite materials with improved combinations of mechanical and physical properties. This study was performed on a new type of IPC called metal porous polymer composite (MPPC) with an interpenetrating network structure. Aluminum-polypropylene (AI-PE) and Aluminum-epoxy resin (Al-Ep) composites were produced by infiltrating the polymer in the aluminum foam. The composite microstructures were characterized using SEM observation. The compressive behavior and energy absorption characteristics of MPPC were investigated and compared with the aluminum foams. The compressive modulus of composite was compared with the VOIGT-REUSS bounds and HASHIN-SHTRIKMAN (H-S) bounds models. The experimental modulus of compressive tests falls well within the theoretical models.

关键词：金属多孔聚合物复合物互穿网络结构压缩行为能量吸收 MPPC复合物

Pose Planning for the End-effector of Robot in the Welding of Intersecting Pipes

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Chinese Journal of Mechanical Engineering 2011年第2期24卷 264-270页

作者： liu yu ZHAO Jing lu Zhenyang CHEN Shujun College of Mechanical Engineering and Applied Electronics Technology Beij＇ing University of Technology Beijing 100124 China

All-position robots are widely applied in the welding of complicated *** of intersecting pipes is one of the most typical *** welding seam is a complicated saddle-like space curve,which puts a great challenge to the pose planning of *** special robots designed specifically for this kind of tasks are rare in China and lack sufficient theoretical *** this paper,a systematic research on the pose planning for the end-effectors of robot in the welding of intersecting pipes is conducted. First,the intersecting curve of pipes is mathematically *** mathematical model of the most general intersecting curve of pipes is derived,and several special forms of this model in degraded situations are also discussed.A new pose planning approach of bisecting angle in main normal plane（BAMNP） for the welding-gun is proposed by using differential geometry and the comparison with the traditional bisecting angle in axial rotation plane（BAARP） method is also analytically *** optimal pose of the welding-gun is to make the orientation posed at the center of the small space formed by the two cylinders and the intersecting curve to help the welding-pool run *** BAMNP method can make sure the pose vertical to the curve and center between the two cylinders at the same time,therefore its performance in welding-technique is superior to the BAARP *** using the traditional BAARP method,the robot structure can become simpler and easier to be controlled,because one degree of freedom（DOF） of the robot can be *** the special case of perpendicular intersecting,an index is constructed to evaluate the quality of welding technique in the process of *** effect of different combination of pipe size on this index is also *** the basis of practical consideration,selection principle for BAARP and BAMNP is *** simulations of those two methods for a serial joint-type robot are made in MATLAB,and the simulation

关键词： pose planning robot all-position welding intersecting pipes bisecting angle welding quality

STUDY ON NEW PASSIVE SCALAR FluX MODEL WITH DIFFUSIVITY OF COMPLEX NUMBER

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Journal of Hydrodynamics 2000年第4期12卷 20-25页

作者： lu Zhi-ming liu yu-lu Cai Shu-tang Shanghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai 200072P.R.China

The turbulent passive scalar fluxes were studied by separately considering the contributions of small eddy motions and large eddy ones. Explicit algebraic approximation was achieved for both small eddy and large eddy scalar fluxes. Especially, the large eddy scalar flux was modelled with complex diffusivity. The singular difficulties in usual algebraic scalar models, do not occur any more in this model. In addition, this new model provides a new way to reasonably describe the negative transport phenomena appearing in asymmetric turbulent flows.

关键词： turbulent passive scalar flux small eddy large eddy negative transport

Some Exact Solutions of Variable Coefficient Cubic-Quintic Nonlinear Schrdinger Equation with an External Potential

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Communications in Theoretical Physics 2009年第3期51卷 391-394页

作者： ZHU Jia-Min liu yu-lu Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China Yiwu Industrial and Commercial College Yiwu 322000 China

By constructing appropriate transformations and an extended elliptic sub-equation approach, we find some exact solutions of variable coefficient cubic-quintie nonlinear Schrodinger equation with an external potential, which include bell and kink profile solitary wave solutions, singular solutions, triangular periodic wave solutions and so on.

关键词： cubic-quintic nonlinear Schrodinger equation variable coefficient exact solution

THE EXTENDED JACOBIAN ELLIPTIC FUNCTION EXPANSION METHOD AND ITS APPLICATIONS IN WEAKLY NONLINEAR WAVE EQUATIONS

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Journal of Hydrodynamics 2006年第3期18卷 352-361页

作者： HUANG Wen-hua liu yu-lu lu Zhi-ming PAN Bo-ying liu Mao-sheng Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China Department of Physics College of Science Huzhou University Huzhou 313000 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China PAN Bo-ying Basic Department YiChun Vocational Technical College Yichun 336000 China

The extended Jacobian elliptic function expansion method is introduced and applied to solve the coupled ZK equations and the coupled KP equations describing two weakly long nonlinear wave models in fluid system. Many types of doubly periodic traveling wave solutions are obtained. Under limiting conditions these solutions are reduced into solitary wave solutions.

关键词： Jacobian elliptic function expansion method,the coupled ZK equation the coupled KP equation

Doubly Periodic Wave Solutions of Jaulent-Miodek Equations Using Variational Iteration Method Combined with Jacobian-function Method

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Communications in Theoretical Physics 2008年第6期49卷 1403-1406页

作者： ZHU Jia-Min lu Zhi-Ming liu yu-lu Department of Computer Yiwu Industrial and Commercial College Yiwu 322000 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

One of the advantages of the variational iteration method is the free choice of initial guess. In this paper we use the basic idea of the Jacobian-function method to construct a generalized trial function with some unknown parameters. The Jaulent-Miodek equations are used to illustrate effectiveness and convenience of this method, some new explicit exact travelling wave solutions have been obtained, which include bell-type soliton solution, kink-type soliton solutions, solitary wave solutions, and doubly periodic wave solutions.

关键词： Jaulent-Miodek equations Jacobian-function method variational iteration method doubly periodic wave solution exact solution

EFFECT OF SWEEP AND EJECTION EVENTS ON PARTICLE DISPERSION IN WALL BOUNDED TURBULENT FLOWS

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Journal of Hydrodynamics 2012年第5期24卷 794-799页

作者： luO Jian-ping lu Zhi-ming QIU Xiang LI Dong-mei liu yu-lu School of Mechanical Engineering Shanghai Institute of Technology Shanghai 200235 China Shanghai Key Laboratory of Mechanics in Energy Engineering and Shanghai Institute of Applied Mathematicsand Mechanics Shanghai University Shanghai 200072 China School of Science Shanghai Institute of Technology Shanghai 200235 China Shanghai Institute of Technology Shanghai 200235 China

This paper studies the sweep and ejection events in a channel flow with Reτ = 80 by using Direct Numerical Simulation （DNS）. The effects of ejection and sweep events on the transport of fluid particles are analyzed separately through a quadrant technique. By analyzing trajectories of the particles released at different wall-normal locations, it is found that the particles from the ejection events mainly move upward while the particles from the sweep events move downward of the flow during short and intermediate diffusion time durations. Numerical results show that the effects of the ejection and sweep events on the mean displacement and the mean square dispersion remain for a long time, one-order of magnitude larger than the streamwise Lagrangian integral ~cales.

关键词： sweep ejection dispersion quadrant analysis turbulent channel flow

Influence of Solvent Size on Structural Properties of Bottle-brush Polymers

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Chemical Research in Chinese Universities 2010年第5期26卷 838-841页

作者： liu Ying-tao liu Hong liu yu-hua lu Zhong-yuan State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun 130021 P. R. China

We proposed a modified dissipative particle dynamics simulation model by which one can effectively avoid the bond-crossing problem, and investigated the effect of solvent size on the structural properties of bottle-brush polymers in dilute solution on the basis of this model. It was found that with the increase of solvent size, the radius of the gyration of the bottle-brush polymer decreases considerably in the athermal solvent but increases in the selective solvent favoring the backbone, respectively.

关键词： Dissipative particle dynamics Bottle-brush polymer Solvent size Bond-crossing

SIMULATION OF LAGRANGIAN DISPERSION USING A LAGRANGIAN STOCHASTIC MODEL AND DNS IN A TURBULENT CHANNEL FLOW

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Journal of Hydrodynamics 2009年第6期21卷 767-773页

作者： luO Jian-ping lu Zhi-ming liu yu-lu School of Mechanical and Automation Engineering Shanghai Institute of Technology Shanghai 200235 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

The mean square displacements of fluid particles in a turbulent channel flow at Reτ = 100 are investigated using a modified Langevin equation, and are compared with DNS results. Both the Lagrangian integral time scales directly obtained from DNS and the predicted values using an empirical relation between the Eulerian and the Lagrangian integral time scales are used in the modified Langevin equation to test the effects of integral time scales on the dispersion of particles. The results show that the slight variation of the Lagrangian integral time scale has little influence on the dispersion. The agreement between results of the model equation and those of DNS is satisfactory except the streamwise dispersion for intermediate times （ 20 〈 t^＋〈 300 ）, where the results of the model equation are slightly overestimated compared to those of DNS. The cause of such discrepancy is discussed.

关键词： turbulent channel flow Lagrangian dispersion Lagrangian stochastic model

Doubly Periodic Propagating Wave Patterns of （2＋1）-Dimensional Maccari System

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Communications in Theoretical Physics 2007年第3期47卷 397-402页

作者： HUANG Wen-Hua liu yu-lu MA Zheng-Yi College of Science Zhejiang Huzhou University Huzhou 313000 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China College of Science Zhejiang Lishui University Lishui 323000 China

Using the variable separation approach, we obtain a general exact solution with arbitrary variable separation functions for the （2＋ 1）-dimensional Maccari system. By introducing Jacobi elliptic functions dn and nd in the seed solution, two types of doubly periodic propagating wave patterns are derived. We invest/gate the wave patterns evolution along with the modulus k increasing, many important and interesting properties are revealed.

关键词： Maccari system variable separation method Jacobi elliptic function periodic wave