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Chinese Journal of Polymer Science 2005年第3期23卷 311-318页

作者： Ji-nanCao IndustrialResearchInstituteSwinburne SwinburneUniversityofTechnologyP.O.Box218HawthornVictoria3122Australia

Direct difference methods have been used to solve the simultaneous non-linear partial differential equations formelt spinning without recourse to linearisation or perturbation *** stability of each difference schemes wasstudied by error analysis using the Taylor series,and by comparison of the results obtained from numerical simulation.withthe logical value in melt *** is found that computation with 19 digit long double precision has significantlysimplified the stability problem of difference *** this method,the precise critical draw ratio of draw resonancein an isothermal and uniform tension spinning of Newtonian fluids can be obtained in between 20.218 and 21.219,a figureconsistent with 20.218 which was obtained by a linear perturbation approximation method by Kase and *** thus haspaved the way to computation of full information for unsteady melt spinning processes using the difference method.

关键词： Draw resonance Melt spinning Newtonian fluid numerical simulation.

numerical simulation.of topography effects on the “00.7” severe rainfall in Beijing

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Progress in Natural Science:Materials International 2005年第9期15卷 818-826页

作者： ZHANG Chaolin1**, JI Chongping1, KUO Yinghwa2, FAN Shuiyong1, XUAN Chunyi3 and CHEN Min1(1. Institute of Urban Meteorology, China Meteorological Administration, Beijing 100089, China 2. Mesoscale and Microscale Meteorology Division, National Center for Atmospheric Research, Boulder, CO 80307-3000, USA 3. Beijing Meteorological Bureau, Beijing 100089, China) Institute of Urban Meteorology China Meteorological Administration Beijing 100089 China Mesoscale and Microscale Meteorology Division National Center for Atmospheric Research Boulder CO 80307-3000 United States Beijing Meteorological Bureau Beijing 100089 China

In an effort to study the severe rainfall event of 4—5th July 2000 in Beijing (with 24h accumulated precipitation of 240 mm), we perform numerical simulation. to investigate this event using the MM5v3.6 model. The model is initialized with the MM5/WRF 3DVAR analysis, which incorporates the ground-based GPS precipitable water vapor, automatic and conventional meteorological observations in its assimilation step. For 24 h accumulated precipitation forecast, the threat scores are 0.72, 0.76, 0.67 and 0.63, for thresholds of 1, 5, 10, and 20 mm, respectively. Holding other factors unchanged, sensitivity experiments were conducted with different topographic resolutions of 110, 50 and 3.7 km to investigate the topographic effects on precipitation over the Beijing area. In these sensitivity experiments, we attempt to preserve the realistic orographic distribution in the model topography under the condition of keeping the dynamic-thermodynamic consistency of the initial model atmosphere to the extent possible. Results indicate that the unique topographic distribution and variations in the Beijing area play an important role in determining the location, distribution and intensity of heavy precipitation.

关键词： topography heavy rainfall 3DVAR ground-based GPS numerical simulation.

A mathematical model for solid liquid and mass transfer coupling and numerical simulation.for hydraulic fracture in rock salt

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Progress in Natural Science:Materials International 2005年第8期15卷 742-748页

作者： LIANG Weiguo 1,2* and ZHAO Yangsheng1(1. Mining Technology Institute, Taiyuan University of Technology, Taiyuan 030024, China 2. Rock and Soil Mechanics Institute, Chinese Academy of Sciences, Wuhan 430071, China) Mining Technology Institute Taiyuan University of Technology Taiyuan 030024 China Rock and Soil Mechanics Institute Chinese Academy of Sciences Wuhan 430071 China

The hydraulic fracture in rock salt is a complicated solid fluid and mass transfer coupling process. Through theoretical analysis, a solid fluid and mass transfer coupling mathematical model of hydraulic fracture in rock salt is established in this work, and numerical simulation. are carried out with the model. The simulation.results indicate that rock salt cracks in the typical way of wing-crack(or tensile crack) during the fracture, and the relation of fracture aperture (w) with expanding distance (x) and fracture time (t) is w=(0.0034+0.0006t)e (0.0007+0.0018t)x. Furthermore, it has been found that both the water pressure in the crack and the expanding velocity of the crack decrease gradually as a result of the influence of salt dissolving during fracturing. These numerical simulation. well illustrate the process of hydraulic fracture in rock salt and are significantly meaningful in engineering practice.

关键词： rock salt hydraulic fracture solid liquid and mass transfer coupling mathematical model numerical simulation.

numerical simulation.of the efficiency of mixing in heterogeneous microchannels with patterned surface potentials

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Progress in Natural Science:Materials International 2006年第12期16卷 1322-1328页

作者： ZHANG Kai~1, LIN Jianzhong~ 1,2 ** and LI Huijun~1(1. State Key Laboratory of Fluid Power Transmission and Control, Zhejiang University, Hangzhou 310027, China 2. China Jiliang University, Hangzhou 310018, China) State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China China Jiliang University Hangzhou 310018 China

The mixing of samples in heterogeneous microchannels with a periodically stepwise surface potential was analyzed numerically using the control volume method. The equations describing the wall potential and external potential were solved first to get the distribution of wall potential and external potential, respectively, then the momentum equation was solved to get the developed flow field. Finally, the mass transport equation was solved to get the concentration field. The simulation.results show that the distribution of samples at the inlet of the microchannel determines its theoretical value of concentration, therefore, the pattern of the distribution of samples at the inlet and its corresponding velocity can be changed to get the desirable concentration of solute. The heterogeneous wall potential almost has no effect on the mixing of samples in two-inlet microfluidic devices. For three-inlet microfluidic devices, the comprehensive ability of transportation and mixing has an optimization when the ratio of periodic length of wall potential to the height of the microchannel is about 4.88. The above conclusions are helpful to the optimization of the design of microfluidic devices.

关键词： microchannel mixing efficiency electroosmosis numerical simulation.

numerical simulation.OF 3-D TURBULENT FLOWS OVER DREDGED TRENCHES

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Acta Mechanica Sinica 1989年第4期5卷 313-322页

作者： Han Guoqi Wang Deguan Xu Xieqing Department of Environmental Engineering, Hohai University, Nanjing Department of Environmental Engineering Hohai University Nanjing

A 3- D free surface flow in open channels based on the Reynolds equations with the k-ε turbulence closure model is presented in this paper. Insted of the 'rigid lid' approximation, the solution of the free surface equation is implemented in the velocity-pressure iterative procedure on the basis of the conventional SIMPLE method. This model was used to compute the flow in rectangular channels with trenches dredged across the bottom. The velocity, eddy viscosity coefficient, turbulent shear stress, turbulent kinetic energy and elevation of the free surface can be obtained. The computed results are in good agreement with previous experimental data.

关键词： 3- D surface water flow model dredged trenches k -ε turbulence model numerical simulation.

numerical simulation.of Microgravity Flame Spread Over Solid Combustibles

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Journal of Thermal Science 1995年第2期4卷 141-149页

作者： JIANGXi FANWeicheng StateKeyLaboratoryofFireScience UniversityofScienceandTechnologyofChinaHefeiAnhui230026China State

A computational model of three-dimensional, time-dependent flame spread in microgravity environment is presented. The solid is assumed to be a thermally-thin, pyrolysing cellulosic sheet. The gas phase model includes the full Navier-Stokes equations with density and pressure variations and six-flus model of radiation heat transfer. The solid phase model consists of continuity and energy eqllations whose solution provides boundary conditions for the gas phase equations. In the numerical procedure, the gas-and solid-phase equations are solved sepaxately and iteratively at each time step. Predictions have been made of flame spread in slow forced flow under gravitational acceleration normal to fuel surface and flame spread in a quiescent environment in an enclosed chamber under gravitational acceleration parallel to fuel surface. numerical simulation. show that, under microgravity, slow-flow conditions, flame spread process is highly unsteady with the upstream flame spreads faster than the downstream flame after a period of ignition. It has also been shown that the level of microgravity has a significant effect on the name spread process.

关键词： microgravity combustion flame spread numerical simulation.

numerical　simulation.OF　THE　EFFECT　OF　FILLET　FORMS　ON　APPENDAGE－BODY　JUNCTION　FLOW

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Journal of Hydrodynamics 1994年第4期6卷 60-73页

作者： Li Ding Zhou Lian-di (China Ship Scientific Research Center P. O. Box 116, Wuxi Jiangsu 214082, P. R. China)

The possibility of using a fillet form to control the horseshoe vortex flow caused by the turbulent shear flow around wing-body junction has been investigated numerically. A numerical method for the solution of three dimensional incompressible, Reynolds-averaged Navier-Stokes equations with the two-equation (k, ε) turbulence model has been developed to evaluate the effect of fillet forms on appendage-body junction vortex flow. The wing investigated is NACA0020. The Reynolds number based on a chordlength is 1. 0 ×105. Three configurations including a baseline, a triangle fillet form, and a constant radius convex arc fillet form along the entire wing/flat-plate junction are presented. It is shown that a suitable convex filet form can significantly improve the stability of junction horseshoe vortex and reduce the strength of vortex and the non-uniformity in the wake velocity profile. It is also demonstrated the capability of the numerical approach in the design of vortex flow control devices.

关键词： fillet form junction flow horseshoe vortex numerical simulation.

numerical simulation.OF NONLINEAR WAVE FLOW AROUND COCHLEA CHANNELED STERN SHIPS

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Journal of Hydrodynamics 1994年第3期6卷 34-46页

作者： Xia Zheng-yu , Shi Zhong-kunHuazhong University of Science and Technology, Wuhan 430074, P. R. China

A nonlinear method based on Gadd's model [1] [2] is developed to simulate the wave flow around cochlea-channeled stern ships. The subsurface division method is capable of dividing the complicated hull into panels and ... 详细信息

关键词： ship forms cochlea-channeled stern ships wave flow numerical simulation.

numerical simulation.of the dual laterolog for carbonate cave reservoirs and response characteristics

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Applied Geophysics 2011年第1期8卷 79-85,96页

作者： Tan Mao-Jin Gao Jie Wang Xiao-Chang Zhang Song-Yang Key Laboratory of Geo-detection （China University of Geosciences） Ministry of Education Beijing 100083 China School of Geophysics and Information Technology China University of Geosciences （Beijing） Beijing 100083 China College of Geophysics and Information Engineering China University of Petroleum （Beijing） Beijing 102249 China SINOPEC Research Institute of Exploration and Production Beijing 100083 China

Cave carbonate formations are characterized by heterogeneity, which makes electrical log prediction difficult. It is currently important to know how to use the dual laterolog to accurately identify and quantitatively evaluate caves. Using numerical simulation.to calculate electrical log responses can provide a theoretical basis for cave identification and evaluation. In this paper, based on the dual laterolog principles, we first study different size spherical cave models using the finite element method （FEM）, determine a relation between resistivity and cave filling after comprehensively studying the log responses of cave models with different filling material, and finally study the dual laterolog responses on caves filled with shale, limestone, conglomerate, and thin laminated formation of sand and shale. The numerical results provide a theoretical basis for identification and evaluation of carbonate cave reservoirs.

关键词： carbonate cave reservoirs dual laterolog finite element method (FEM) numerical simulation.

numerical simulation.of Hot Spot Growth in Detonation with Regard to the Turbulent Mechanism of Energy Transfer

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Journal of Physical Science and Application 2015年第3期5卷 226-237页

作者： Yury Vasilyevich Yanilkin Vitaly Grigoryevich Morozov Irina Isorevna Karpenko Olga Nikolaevna Chernyshova Russian Federal Nuclear Centre VNIIEF Sarov 607200 Russia

The paper presents the results of numerical modeling of hot spot growth process in detonation with account for turbulent mixing. The performed investigation has shown that large-scale HE （High explosives） particles mix up and split down to smaller sizes in the result of shock wave impact, instability development on the HE-EP （Explosion product） interface and vortex flow; at these sizes, due to the developed surface of the HE-EP contact, HE has enough time to get heated （energy transfer from EP）, and the decomposition reaction effectively continues. numerical modeling make the calculation of the hot spot growth rate （about 100-200 m/s） possible. This has proved the hypothesis saying that at mechanical material transport the turbulence in the reaction zone plays an important role and it must be taken into account in the detonation theory.

关键词： Hot spot detonation turbulent mixing numerical simulation.