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Science china(physics,Mechanics & Astronomy) 2010年第12期53卷 905-914页

作者： wang Tao,BAI JingSong,LI Ping & LIU Kun institute of fluid physics,china academy of engineering physics,mianyang 621900,china institute of fluid physics China Academy of Engineering Physics Mianyang China

A parallel algorithm and code MVFT(multi-viscous-fluid and turbulence) of large-eddy simulation(LES) is developed from our MVPPM(multi-viscous-fluid piecewise parabolic method),and performed to solve the multi compressible Navier-Stokes(N-S) *** effect of the unresolved subgrid-scale(SGS) motions on the large scales is represented by different SGS stress models in LES.A Richtmyer-Meshkov instability experiment of the evolution of a rectangular block of SF6,which occupies half of the height of the shock tube test section,following the interaction with a planar shock wave,is numerically and exhaustively simulated by this *** comparison between experimental and simulated images of the evolving SF6 block shows that they are *** numerical simulations reproduce the complex developing process of SF6 block,which grows *** geometric quantities that characterize the extents of SF6 block are also compared in detail between numerical simulations and experiment with good agreements between them,a quantitative demonstration of the developing law of SF6 *** is an evident discrepancy between the three numerical simulations for the maximum position of the right edge of block at the late stage,because the right interface grows complicated and the dissipation is different for different SGS *** SGS turbulent dissipation,molecular viscosity dissipation and SGS turbulent kinetic energy have been studied and *** have a similar distribution to the large eddy *** SGS turbulent dissipation is much greater than the molecular viscosity dissipation;the SGS turbulent dissipation of Vreman model is smaller than the Smagorinsky *** general,the simulated results of Vreman SGS model are better compared with the dynamic viscosity and Smagorinsky SGS *** vorticity and circulation deposition on the block interface have also been investigated.

关键词： large-eddy simulation Navier-Stokes equations subgrid-scale Richtmyer-Meshkov instability turbulent dissipation turbulent kinetic energy circulation deposition

Large eddy simulation of a shocked gas cylinder instability induced turbulence

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Science china(physics,Mechanics & Astronomy) 2010年第9期53卷 262-268页

作者： LI Ping,BAI JingSong,wang Tao & ZOU LiYong National Key Laboratory for Shock Wave and Detonation physics Research,institute of fluid physics,CAEP,mianyang 621900,china National Key Laboratory for Shock Wave and Detonation physics Research Institute of Fluid Physics CAEP Mianyang China

The Navier-Stokes equations for compressible fluid are solved with the operator splitting technique and LES (large eddy simulation) with the Smagorinsky model. A computational code MVFT (multi-viscosity-fluid and turbulence) is developed to study hydrodynamic instability and the induced turbulent mixing for multi compressible fluid. In order to validate the code MVFT,the LANL's shock tube experiment of shocked SF6 gas cylinder is simulated with the initial state of SF6 gas cylinder described by dissipative ITL (interface transition layer). It is shown that the width and height of gas cylinder calculated with MVFT are closer to the experimental results than RAGE,and that the velocities of upstream edge,downstream edge and vortex edge agree with the experimental results,and are appreciably smaller than the RAGE results. The code MVFT has been pre-liminarily validated.

关键词： Richtmyer-Meshkov instability large eddy simulation Navier-Stokes equations turbulence model

Transient Behavior of Negative Hydrogen Ion Extraction from Plasma

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Plasma Science and Technology 2013年第9期15卷 945-949页

作者：蓝朝晖institute of fluid physics china academy of engineering physics 彭宇飞杨振龙继东 institute of fluid physics China Academy of Engineering Physics

For plasma source, the extraction of negative ions is quite different from that of positive ions. To understand the effect of extraction field on plasma, the time-dependent behavior of negative hydrogen ion extraction from a negative ion source has been studied by particle-in-cell simulation in the collisionless limit. The simulations have shown that, due to the difference in dynamics between electrons and ions, the imbalance of the numbers of charged particles occurs in the source, results in the broadening of plasma sheath and the great increase of plasma potential. The resultant high sheath field and the ambipolar electric field in plasma make the negatively charged particles congregate inside the sheath and move toward the extraction outlet. The emission area of negative ions is much smaller than that of the extraction aperture, which is in sharp contrast to the case of positive ion extraction.

关键词： negative hydrogen ion particle-in-cell simulation ion source ion extraction

Effects of viscosity on shock-induced damping of an initial sinusoidal disturbance

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Science china(physics,Mechanics & Astronomy) 2010年第5期53卷 802-806页

作者： MA XiaoJuan1,LIU FuSheng1 & JING FuQian2 1 College of Physical Science and Technology,Southwest Jiaotong University,Chengdu 610031,china 2 Laboratory for Shock Wave and Detonation physics Research,institute of fluid physics,Chinese academy of engineering physics,mianyang 621900,china College of Physical Science and Technology Southwest Jiaotong University Chengdu China Laboratory for Shock Wave and Detonation physics Research Institute of Fluid Physics Chinese Academy of Engineering Physics Mianyang China

A lack of reliable data treatment method has been for several decades the bottleneck of viscosity measurement by disturbance amplitude damping method of shock *** this work the finite difference method is firstly applied to obtain the numerical solutions for disturbance amplitude damping behavior of sinusoidal shock front in inviscid and viscous *** water shocked to 15 GPa is taken as an example,the main results are as follows:(1) For inviscid and lower viscous flows the numerical method gives results in good agreement with the analytic solutions under the condition of small disturbance(a0/λ=0.02);(2) For the flow of viscosity beyond 200 Pa s(η=κ) the analytic solution is found to overestimate obviously the effects of *** is attributed to the unreal pre-conditions of analytic solution by Miller and Ahrens;(3) The present numerical method provides an effective tool with more confidence to overcome the bottleneck of data treatment when the effects of higher viscosity in experiments of Sakharov and flyer impact are expected to be analyzed,because it can in principle simulate the development of shock waves in flows with larger disturbance amplitude,higher viscosity,and complicated initial flow.

关键词： viscosity coefficient two-dimensional Eulerian flow shock front sinusoidal disturbance

The critical behavior of shear modulus in solid-liquid mixing phase

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Science china(physics,Mechanics & Astronomy) 2007年第6期50卷 742-746页

作者： RAN XianWen1,2,TANG WenHui1,TAN Hua2 & DAI ChengDa2 1 institute of Technological physics,College of Science,National University of Defense Technology,Changsha 410073,china 2 Laboratory for Shock Wave and Detonation physics Research,institute of fluid physics,Chinese academy of engineering physics (CAEP),mianyang 621900,china institute of Technological physics College of Science National University of Defense Technology Changsha China Laboratory for Shock Wave and Detonation physics Research Institute of Fluid Physics Chinese Academy of Engineering Physics (CAEP) Mianyang China

The behavior of shear modulus in solid-liquid mixing phase has been discussed and analyzed. The result was concluded that shear modulus went to zero as the melting mass ratio attained a critical value. The percolation theory model we pro-posed showed that this value was about 0.68742. The melting-induced destabilizing factor of material proposed by us can represent phenomenologically the change of shear modulus in melting process.

关键词： solid-liquid mixing phase, critical behavior, shear modulus, destabilizing factor The behavior of shear modulus in solid-liquid mixing phase has been discussed and analyzed. The result was concluded that shear modulus went to zero as the melting mass ratio attained a critical value. The percolation theory model we proposed showed that this value was about 0.68742. The melting-induced destabilizing factor of material proposed by us can represent phenomenologically the change of shear modulus in melting process.……

A first-principles investigation into the hydrogen bond interaction in β-HMX

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Science china(physics,Mechanics & Astronomy) 2010年第6期53卷 1080-1085页

作者： CHEN Fang 1 ,ZHANG Hong 1,2,ZHAO Feng 3 ,MENG ChuanMin 3 & CHENG XinLu 1 1 institute of Atomic and Molecular physics,Sichuan University,Chengdu 610065,china 2 School of Physical Science and Technology,Sichuan University,Chengdu 610065,china 3 Laboratory for Shock Wave and Detonation physics Research,Southwest institute of fluid physics,china academy of engineering physics,mianyang 621900,china institute of Atomic and Molecular physics Sichuan University Chengdu China School of Physical Science and Technology Sichuan University Chengdu China Laboratory for Shock Wave and Detonation physics Research Southwest Institute of Fluid Physics China Academy of Engineering Physics Mianyang China

A theoretical study of structural and electronic properties of β-HMX crystal is performed using density-functional theory(DFT). The total density of states(TDOS) is presented. The atomic orbit projected density of state(PDOS) from the p-type orbit of C,N,O and the s-type orbit of H is discussed. The study by analyzing the PDOS shows that the structure of β-HMX crystal possesses C-H···O intra- and inter-molecular hydrogen-bonding. There exists a hydrogen bonding between H5 -1s and O12 -2p orbits,between H19 -1s and O28 -2p orbits of intra molecules,and between H19 -1s and O24 -2p orbits of inter molecules. The Mulliken population analysis is also made.

关键词： structural property hydrogen bond β-HMX population analysis

Existence and Uniqueness of Stationary Solutions of Non-Newtonian Viscous Incompressible fluids

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Communications in Nonlinear Science and Numerical Simulation 1999年第1期4卷 63-68页

作者： Boling GUO* and Guoguang LIN**,+ (institute of Applied physics and Computational Mathematics, Beijing 100088, china) Guoguang LIN (Graduate School of china academy of engineering physics, Beijing 100088, china) + (Department of Mathematics, Yunnan Unive Inst. Appl. Phys. and Compl. Math. Beijing 100088 China Graduate School China Academy of Engineering Physics Beijing 100088 China Department of Mathematics Yunnan University Kunming 650091 China

The existence and uniqueness of stationary solution a bipolar incompressible viscous fluids is *** is also obtained that the every solution of the system converges to the stationary solution as time t → ∞.

关键词： non-Newtonian fluid stationary solution, asymptotic behavior bipolar fluid

Vibrational relaxation dynamics in transient grating spectroscopy studied by rate equations based on time-dependent correlation function

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Chinese physics B 2012年第4期21卷 245-248页

作者：于国洋宋云飞何兴郑贤旭谭多旺陈军杨延强 Center for Condensed Matter Science and Technology Department of PhysicsHarbin Institute of TechnologyHarbin 150001China National Key Laboratory of Shock Wave and Detonation physics Institute of Fluid PhysicsChina Academy of Engineering PhysicsMianyang 621900China

A modified model, a set of rate equations based on time-dependent correlation function, is used to study vibrational relaxation dynamics in transient grating spectroscopy. The dephasing, the population dynamics, and the vibrational coherence concerning two vibrational states are observed respectively in organic dye IR780 perchlorate molecules doped polyvinyl alcohol matrix. The result shows that in addition to the information concerning system-environment interaction and vibrational coherence, the vibrational energy transfer can be described by this modified model.

关键词： transient grating population dynamics vibrational energy transfer

Weak Periodic Solutions of Non-Newtonian Viscous Incompressible fluids

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Communications in Nonlinear Science and Numerical Simulation 1999年第1期4卷 56-60页

作者： Boling GUO* and Guoguang LTN** (institute of Applied physics and Computational Mathematics, Be1Jing 100088, china) and Guoguang LTN (Graduate School of china academy of engineering physics, Beijing 100088, china) + (Department of Mathematics, Yunnan Univ Inst. Appl. Phys. and Compl. Math. Beijing 100088 China Graduate School China Academy of Engineering Physics Beijing 100088 China Department of Mathematics Yunnan University Kunming 650091 China

The existence of weak periodic solution in time of non-Newtonian fluids with a time periodic forcing is established.

关键词： periodic solution weak periodic solution bipolar fluid