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NUMERICAL SIMULATION OF SLOSHING IN RECTANGULAR TANK WITH VOF BASED ON UNSTRUCTURED GRIDS

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Journal of Hydrodynamics 2010年第6期22卷 856-864页

作者： MING Ping-jian DUAN Wen-yang college of Power and Energy engineering Harbin Engineering University Harbin 150001 China college of Shipbuilding engineering Harbin Engineering University Harbin 150001 China

A new method for sloshing simulation in a sway tank is present, in which the two phase interface is treated as a physical discontinuity, which can be captured by a well-designed high order scheme. Based on Normalized Variable Diagram （NVD）, a high order discretization scheme with unstructured grids is realized, together with a numerical method for free surface flow with a fixed grid. This method is implemented in an in-house code General Transport Equation Analyzer （ GTEA ） which is an unstructured grids finite volume solver. The present method is first validated by available analytical solutions. A simulation for a 2-D rectangular tank at different excitation frequencies of the sway is carried out. A comparison with experimental data in literature and results obtained by commercial software CFX shows that the sloshing load on the monitor points agrees well with the experimental data, with the same grids, and the present method gives better results on the secondary peak. It is shown that the present method can simulate the free surface overturning and breakup phenomena.

关键词： sloshing numerical simulation unstructured grid Volume Of Fluid (VOF)

NUMERICAL SIMULATION AND EXPERIMENTAL RESEARCH ON HYDRAULIC COUNTER-PRESSURE DEEP DRAWING OF CONICAL PART

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Chinese Journal of Mechanical engineering 2001年第1期14卷 94-96页

作者： Tang Jinglin Nie Shaomin college of Mechanical engineering,Yanshan University 燕山大学机械工程学院河北秦皇岛

Hydraulic counter pressure deep drawing of truncated conical part is numerically simulated with MARK and the nature of increasing the forming limit in this process is *** effects of blank holding force and chamber pressure on forming results are investigated by experiments and,as a result,truncated conical parts with large drawing ratio are successfully formed in single step with this drawing method.

关键词： Hydraulic counter pressure deep drawing Numerical simulation Truncated conical part

STUDY ON THE MATHEMATICAL MODEL FOR DRILL WANDERING MOTION

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Chinese Journal of Mechanical engineering 2000年第1期13卷 58-63页

作者： Zhou Zhixiong Lin Cheng (college of Mechanical and Automotive engineering, Hunan University) 湖南大学湖南长沙

Based on the kinematic relationship of the drill, drill point and workpiece and the coordinate systems founded,the mathematical models of the drill point wandering motion for the drill initial penetration, i. e. the formulae for the drill point center locus, hole shape and cutting edge locus, are established. According to these formulae the hole shape to be made is simulated and analyzed. It is verified that the bending chatter of the drill during the drill penetrating is the main cause to form a polygon like hole.

关键词： Drill point Initial penetration Wandering motion Mathematical model

New discrete element models for elastoplastic problems

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Acta Mechanica Sinica 2009年第5期25卷 629-637页

作者： Ming Cheng Weifu Liu Kaixin Liu LTCS and Department of Mechanics and Aerospace engineering,college of engineering, Peking University, 100871 Beijing, China LTCS and Department of Mechanics and Aerospace engineering College of Engineering Peking University 100871 Beijing China

The discrete element method （DEM） has attractive features for problems with severe damages, but lack of theoretical basis for continua behavior especially for nonlinear behavior has seriously restricted its application. The present study proposes a new approach to developing the DEM as a general and robust technique for modeling the elastoplastic behavior of solid materials. New types of connective links between elements are proposed, the interelement parameters are theoretically determined based on the principle of energy equivalence and a yield criterion and a flow rule for DEM are given for describing nonlinear behavior of materials. Moreover, a numerical scheme, which can be applied to modeling the behavior of a continuum as well as the transformation from a continuum to a discontinuum, is obtained by introducing a fracture criterion and a contact model into the DEM. The elastoplastic stress wave propagations and the tensile failure process of a steel plate are simulated, and the numerical results agree well with those obtained from the finite element method （FEM） and corresponding experiment, and thus the accuracy and efficiency of the DEM scheme are demonstrated.

关键词： DEM Continuum Plasticity Fracture

Laser Surface Hardening of 9CrSi Steel

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Journal of Materials Science & Technology 2002年第1期18卷 17-20页

作者： Nunghee RYU and Sunggoon KANGDivision of Materials Science and engineering, college of engineering, Hanyang University, Korea [ Manuscript received August 7, 2001, in revised form September 20, 2001] Div. of Mat. Sci. and Eng. Coll. of Eng. Hanyang Univ. Hanyang South Korea

The effects of laser hardening parameters such as beam power, beam diameter and scanning rate on microstructure and hardness of 9CrSi steel were investigated. The microstructure of the surface layer of 9CrSi steel was changed from pearlite to martensite, retained austenite and carbide by laser hardening. The depth of the hardened layer increased with increasing laser energy density and the surface hardeness increased by 3-5 times as high as the untreated steel. The laser hardened surface had good wear resistance due to martensite and carbide in the surface layer. The wear mode at low speed was abrasive, while the wear mode at high speed was adhesive.

关键词： Laser hardening Martensite Hardeness Phase trasformation

Particle swarm optimization with a leader and followers

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Progress in Natural Science:Materials International 2008年第11期18卷 1437-1443页

作者： Junwei Wang Dingwei Wang Institute of Systems engineering,college of Information Science and engineering,Northeastern University,Shenyang 110004,China Institute of Systems engineering College of Information Science and Engineering Northeastern University Shenyang 110004 China

Referring to the flight mechanism of wild goose flock,we propose a novel version of Particle Swarm Optimization(PSO)with a leader and *** is referred to as Goose Team Optimization(GTO).The basic features of goose team flight such as goose role division, parallel principle,aggregate principle and separate principle are implemented in the recommended *** GTO,a team is formed by the particles with a leader and some *** role of the leader is to determine the search *** followers decide their flying modes according to their distances to the leader ***,a wide area can be explored and the particle collision can be really *** GTO is applied to four benchmark examples of complex nonlinear functions,it has a better computation perfor- mance than the standard PSO.

关键词： Particle swarm optimization Goose team optimization Role division Parallel principle Aggregate principle Separate principle

STUDY ON SHIFT SCHEDULE AND SIMULATION OF AUTOMATIC TRANSMISSION

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Chinese Journal of Mechanical engineering 2001年第3期14卷 250-253页

作者： Gong Jie,Zhao Dingxuan (college of Mechanical Science and engineering ,Jilin University) 吉林大学机械科学与工程学院吉林长春

From the point of view of saving energy, a new shift schedule and auto-controlling strategy for automatic transmission are proposed. In order to verify this shift schedule, a simulation program using a software package of Matlab/ Simulink is developed. The simulation results show the shift schedule is correct. This shift schedule has enriched the theory of vehicle automatic maneuvering and will improve the efficiency of hydrodynanic drive system of the vehicle.

关键词： engineering vehicle Automatic transmission Shift schedule Simulation Saving energy

New method for passive radar seeker to antagonize non-coherent radar decoy

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Journal of Systems engineering and Electronics 2010年第3期21卷 397-403页

作者： Weijian Si,Xicai Si,and Zhiyu Qu college of Information and Communication engineering,Harbin engineering University,Harbin 150001,P.R.China college of Information and Communication engineering Harbin Engineering UniversityHarbin 150001P.R.China

Using super resolution direction of arrival（DOA） estimation algorithm to reduce the resolution angle is an effective method for passive radar seeker（PRS） to antagonize non-coherent radar *** the power and correlation property between radar and non-coherent decoy,an improved subspace DOA estimation method based on traditional subspace algorithm is *** this new method uses the invariance property of noise subspace,compared with traditional MUSIC algorithm,it shows not only better resolution in condition of closely spaced sources,but also superior performance in case of different power or partially correlated *** this new method,PRS can distinguish radar and non-coherent decoy with good *** the simulation result and the experimental data confirm the performance of the method.

关键词： radar countermeasures passive radar seeker(PRS) non-coherent decoy direction of arrival(DOA) estimation.

MOTION ANALYSIS AND DESIGN OF ACCUMULATOR FOR HYDRAULIC ROCK DRILL

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中国有色金属学会会刊：英文版 1996年第2期6卷 148-151页

作者： Liu Shixun(college of Mechanical and Electrical engineering, Central South University of Technology, Changsha 410083) CENT S UNIV TECHNOL COLL MECH & ELECT ENGNCHANGSHA 410083PEOPLES R CHINA

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关键词： hydraulic accumulator diaphragm service life stretching ratio parameter design,motion analvsis