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Plasma Science and Technology 2023年第4期25卷 23-32页

作者：汤炜康栾其斌孙宏恩魏来路爽爽姜帅徐健王正汹 Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024Peopleʼs Republic of China Key Laboratory of Geospace Environment University of Science and Technology of ChinaHefei 230026Peopleʼs Republic of China Faculty of Electronic Information and Electrical Engineering Dalian University of TechnologyDalian 116024Peopleʼs Republic of China

Numerical simulation on the resonant magnetic perturbation penetration is carried out by the newly-updated initial value code MDC(MHD@Dalian Code).Based on a set of two-fluid fourfield equations,the bootstrap current,parallel,and perpendicular transport effects are included *** into account the bootstrap current,a mode penetration-like phenomenon is found,which is essentially different from the classical tearing mode *** reveal the influence of the plasma flow on the mode penetration process,E×B drift flow and diamagnetic drift flow are separately applied to compare their *** results show that a sufficiently large diamagnetic drift flow can drive a strong stabilizing effect on the neoclassical tearing ***,an oscillation phenomenon of island width is *** analyzing it in depth,it is found that this oscillation phenomenon is due to the negative feedback regulation of pressure on the magnetic *** physical mechanism is verified again by key parameter scanning.

关键词： tokamak two-fluid NTM

A Discontinuous Galerkin Method for Ideal two-fluid Plasma Equations

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Communications in Computational Physics 2011年第2期9卷 240-268页

作者： John Loverich Ammar Hakim Uri Shumlak Tech-X Corporation 5621 Arapahoe Avenue Suite ABoulder CO80303USA University of Washington Aerospace and Energetics Research ProgramSeattleWA 98195-2250USA

A discontinuous Galerkin method for the ideal 5 moment two-fluid plasma system is *** method uses a second or third order discontinuous Galerkin spatial discretization and a third order TVD Runge-Kutta time stepping *** method is benchmarked against an analytic solution of a dispersive electron acoustic square pulse as well as the two-fluid electromagnetic shock[1]and existing numerical solutions to the GEM challenge magnetic reconnection problem[2].The algorithm can be generalized to arbitrary geometries and three *** approach to maintaining small gauge errors based on error propagation is suggest.

关键词： Plasma two-fluid 5 moment discontinuous Galerkin electrostatic shock electromagnetic shock magnetic reconnection

The two-fluid Model of Turbulent Buoyant Recirculating two-Phase Flow

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Science China Mathematics 1993年第9期36卷 1129-1139页

作者：沈永明赵文谦倪浩清 Department of Civil Engineering Dalian University of TechnologyDalian 116023PRC Department of Hydraulic Engineering Chengdu University of Science and TechnologyChengdu 610065PRC Institute of Water Conservancy and Hydroelectric Power Research Beijing 100044PRC

Taking refined forecasting model of oil pollution as basic target,this pa-per widely deals with the theory and method of refined simulation of turbulent *** two-fluid model of turbulent buoyant recirculating two-phase flow and the cor-responding method of numerical computation are developed in this *** motion ofeach phase is described by a unified multi-fluid model in an Eulerian coordinate *** laws of turbulent transportation for each phase,and the restriction of each other be-tween the two phases are completely *** complex two-phase turbulence withbuoyancy and recirculating flow is selected to examine *** of the re-sults of numerical simulation with the experimental data is *** the forecastsfor oil-water two-phase turbulence are carried *** has been shown that the results ofnumerical simulation are satisfactory.

关键词： two-phase turbulence two-fluid model predietion of oil pollution

two-fluid oscillatory flow in a channel

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Theoretical & Applied Mechanics Letters 2011年第3期1卷 71-73页

作者： C.Y.Wang Departments of Mathematics and Mechanical Engineering Michigan State University

The validity of Navier’s partial slip condition is investigated by studying the oscillatory flow in a coated *** two-fluid model is used to solve the unsteady viscous equations *** slip is experienced by the core ***... 详细信息

关键词： Navier's condition slip two-fluid oscillatory

Experimental Determination and Modeling of Bubble Size Distributions in Bubble Columns

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Chinese Journal of Chemical Engineering 1998年第1期6卷 33-45页

作者： H.F.Svendsen 罗和安 K.W.Hjarbo H.A.Jakobsen Department of Chemical Engineering Norwegian University of Science and Technology Department of Chemical Engineering Xiangtan University SINTEF Applied Chemistry DNMI P.O.Box 43Blindern

Using a five point conductivity technique local values of bubble size,bubble velocity and gas fractionhave been experimentally determined in a 288 mmID and 4.3 m high bubble column as a function of axial andradial position for the air/water and CO2/N2/aqueous MDEA *** experimental results are comparedwith predictions from a fundamental two-fluid *** implementation of a non-steady lateral drag term inthe two-fluid model has been *** addition to improving the physical realism of the model,it is found togive slight improvements in the predictions of the distributions of local bubble *** of bubble size arefound in reasonable agreement with experimental values in the heterogeous flow regime,whereas they are stil1found to be unreliable at low gas *** void predictions are found in reasonable agreement with experi-mental values,but deviations occur in the homogeneous flow regime towards the *** is attributed to defi-ciencies in the simplified bubble size

关键词： Bubble column bubble size distribution volumetric velocity gas fraction two-fluid model

Effects of diamagnetic drift on nonlinear interaction between multi-helicity neoclassical tearing modes

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Chinese Physics B 2024年第6期33卷 452-458页

作者：王海源姜帅刘桐魏来栾其斌王正汹 Key Laboratory of Materials Modification by Laser Ionand Electron Beams of the Ministry of EducationSchool of PhysicsDalian University of TechnologyDalian 116024China Faculty of Electronic Information and Electrical Engineering Dalian University of TechnologyDalian 116024China

A numerical study of the diamagnetic drift effect on the nonlinear interaction between multi-helicity neoclassical tearing modes(NTMs) is carried out using a set of four-field equations including two-fluid *** results show that,in contrast to the single-fluid case,5/3 NTM cannot be completely suppressed by 3/2 NTM with diamagnetic drift *** modes exhibit oscillation and coexist in the saturated *** better understand the effect of the diamagnetic drift flow on multiple-helicity NTMs,the influence of typical relevant parameters is *** is found that the average saturated magnetic island width increases with increasing bootstrap current fraction f_(b) but decreases with the ion skin depth δ.In addition,as the ratio of parallel to perpendicular transport coefficients χ_(‖)/χ_(⊥) increases,the average saturated magnetic island widths of the 3/2 and 5/3 NTMs *** underlying mechanisms behind these observations are discussed in detail.

关键词： tokamak two-fluid neoclassical tearing modes multi-helicity

Influence of Solids Circulation Flux on Coal Gasification Process in a Pressurized High-density Circulating fluidized Bed

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Journal of Thermal Science 2019年第1期28卷 97-105页

作者： ZHANG Yawen LEI Fulin XIAO Yunhan Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) School of Chemical Engineering and Technology Tianjin University Key Laboratory of Advanced Energy and Power Institute of Engineering Thermophysics Chinese Academy of Sciences University of Chinese Academy of Sciences

The coal gasification behaviors in the pressurized high-density circulating fluidized bed under various solids circulation fluxes were studied with the CFD method, which combines the two-fluid model and coal gasification reactions represented by the chemical percolation devolatilization and the MGAS models. The numerical method was validated with two experimental cases, and detailed distributions of gas species and temperature in the riser were illustrated to understand the gasification process. To fully understand the influence of solids circulation flux on the gasification behavior, a series of cases were simulated with the solids flux varying gradually from 260 to 1010 kg/m^2 s, and the composition and quality of syngas were compared between various cases. The higher heating value of syngas firstly increased and then decreased with the increase of solids flux, and it reached the highest value around 480 kg/m^2 s. The influence of solids flux on gasification process was further analyzed through the contours of temperature, solids concentration, and gas composition in the riser.

关键词： CFD two-fluid model gasification high-density CFB

Numerical simulations of gas-particle flow behavior created by low-level rotary-winged aircraft flight over particle bed

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Applied Mathematics and Mechanics(English Edition) 2019年第3期40卷 397-406页

作者： Xiaoxue JIANG Yingqiao XU Chuang WANG Linzhi MENG Huilin LU School of Energy Science and Engineering Harbin Institute of Technology Fifth Research Institute China Aerospace Science and Technology Corporation

The aerodynamics of gas-particle suspensions is simulated as an Euler-Euler two-fluid model in a revolving rotor over a particle bed. The interactions of collisions between the blade and particles and particle-particle interactions are modeled using the kinetic theory of granular flow(KTGF). The gas turbulence induced by the rotation of the rotor is modeled using the kg-εg model. The flow field of a revolving rotor is simulated using the multiple reference frame(MRF) method. The distributions of velocities, volume fractions, and gas pressure are predicted while the aircraft hovers at different *** gas pressure decreases from the hub to the tip of the blade, and it is higher at the pressure side than that at the suction side of the rotor. The turbulent kinetic energy of the gas increases toward the blade tip. The volume fraction of particles decreases as the hovering altitude increases. The simulated pressure coefficient is compared with that in experimental measurements.

关键词： helicopter rotor Euler-Euler two-fluid model kinetic theory of granular flow(KTGF) pressure coefficient

A three-dimensional k-ε-k_p model in curvilinear coordinates for sediment movement and bed evolution

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Science China(Technological Sciences) 2009年第4期52卷 1090-1100页

作者： SHEN YongMing1 & LIU Cheng2 1 State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116023, China 2 Pearl River Hydraulic Research Institute, Guangzhou 510611, China State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian China Pearl River Hydraulic Research Institute Guangzhou China

To aim at the substitution of the magnitude and direction of water flow movement near bed for those of bed load transport in solid-liquid two-phase one-fluid model, and to simulate the effect of secondary flow on transverse bed load transport in channel bends and the effect of bed slope on bed load trans- port in a better way, a three-dimensional k-ε-kp solid-liquid two-phase two-fluid model in curvilinear coordinates is solved numerically with a finite-volume method on an adaptive grid for studying wa- ter-sediment movements and bed evolution in a 120° channel bend. Numerical results show that the trajectories of solid-phase deviate from those of liquid-phase in the channel bend, and the deviation increases with the increase of the particle diameters. The calculated bed deformation by the k-ε-kp model is in better agreement with measured bed deformation than those by one-fluid model. It is proved that the k-ε-kp model can simulate the effect of secondary flow on lateral bed load transport with the higher accuracy than the one-fluid model.

关键词： curvilinear coordinates three-dimensional k-ε-kp model two-fluid model solid-liquid flows channel bend bed load bed evolution tra- jectory

Numerical simulation of micro-bubble drag reduction of an axisymmetric body using OpenFOAM

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Journal of Hydrodynamics 2019年第5期31卷 900-910页

作者： Xiao-jie Zhao Zhi Zong Yi-chen Jiang Yu Pan School of Naval Architecture Dalian University of TechnologyDalian 116024China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian 116024China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Dalian 116024China Liaoning Engineering Laboratory for Deep-Sea Floating Structures Dalian 116024China

The two-phase micro-bubble flow over an axisymmetric body is investigated using the OpenFOAM *** numerical model consists of an Eulerian-Eulerian two-fluid model with closure relationships for the interfacial momentum transfer to capture the multiphase flow,a standard A:-￡*model for the continuous phase and one turbulence model inside the OpenFOAM for the dispersed *** bubble sizes are calculated based on the solution of the transport equation of the interfacial area *** simulations in this work are carried out with different air injection rates and different flow *** effects of bubble size on drag reduction are *** numerical results are compared against some available experiments and other numerical *** numerical results indicate that the airflow rate and air volume fraction within the boundary layer near the body play important roles in micro-bubble drag *** frictional drag reduction effect by micro bubbles is larger for lower water speed,and the presence of the micro bubbles can increase the pressure resistance of the *** reduction rates are generally higher when the bubble diameter is smaller.

关键词： Eulerian-Eulerian two-fluid model axisymmetric body micro bubbles drag reduction numerical simulation