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Large-eddy simulations of the Richtmyer-Meshkov instability of rectangular interfaces accelerated by shock waves

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

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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

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Inhibit the Porosity with Electron Beam Scanning Method in Welding LD10 Aluminum Alloy

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稀有金属材料与工程 2011年第S4期40卷 54-57页

作者： Mo Zhonghai,Wang Yarong,Huang Wenrong Institute of Machinery Manufacturing Technology,China Academy of Engineering Physics,mianyang 621900,China China Acad Engn Phys Inst Machinery Mfg Technol Mianyang 621900 Peoples R China

LD10 aluminum alloy is becoming widely used in aeronautics and astronautics industries for the advantages of high specific strength and good mechanical *** alloy is an active metal with low melting point and boiling *** porosity is apt to occur in the processing of electron beam *** this article,the author investigated the influence of electron beam scanning welding parameters (scanning figure,scanning frequency,focus,and welding speed) on porosity.10 mm thick LD10 aluminum alloy were welded and then tested by X-ray *** experiment results indicated that rational parameters would reduce the occurrence opportunity of *** the parameters of circle scanning,high scanning frequency,focus-out,and smaller welding speed,the porosity can be significantly reduced.

关键词： electron beam welding LD10 aluminum alloy porosity

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Processing technique of target capsule's micro inflation hole with a scanning probe

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Science China(Technological Sciences) 2004年第1期47卷 77-84页

作者： SUN Tao, YAN Yongda, GAO Dangzhong, TANG Yongjian, FU Yibei & DONG ShenPrecision Engineering Research Institute, Harbin Institute of Technology, Harbin 150001, China Research Centre of Laser Fusion, Chinese Academy of Engineering Plysics, mianyang 621900, China Institute of Nuclear Physics and Chemistry, Chinese Academy of Engineering Physics, mianyang 621900, China Precision Engineering Research Institute Harbin Institute of Technology Harbin China Research Centre of Laser Fusion Chinese Academy of Engineering Plysics Mianyang China Institute of Nuclear Physics and Chemistry Chinese Academy of Engineering Physics Mianyang China

To resolve inflation of inertial confinement fusion (ICF) target and encapsulation of micro inflation hole with adhesive, a scanning probe microscope (SPM) diamond microprobe was used as the cutting tool with SPM in contact mode. Some parameters influencing the quality of micro inflation hole, such as the scanning direction of the diamond tip, the scanning rate and the contact force are discussed. Accurate taper hole was achieved whose dimension and precision could meet the requirements of inflation and encapsulation technique of micro hole. The experimental results show that using SPM diamond microprobe as the cutting tool and with special processing technique, the precision machining of target capsule's taper inflation hole can be realized. A novel operative technology for filling high Z gas to target is provided.

关键词： target capsule, scanning probe microscope (SPM), diamond microprobe, processing technique, brittle material.

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Trace tritium recovery from the residue of liquid Li_(17)Pb_(83) alloy

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Science China Chemistry 2010年第8期53卷 1825-1828页

作者： XIE Bo,YANG TongZai & WENG KuiPing Institute of Nuclear Physics and Chemistry,China Academy of Engineering Physics,mianyang 621900,China Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang China

The liquid Li17Pb83 alloy is a prominent breeder material for use in a fusion *** the design of an effective tritium extraction system for the liquid lithium lead bubbler of the test blanket module of such a reactor,finding ways to strictly limit the losses of tritium and to minimize radioactive risks is very *** this purpose,the isotope exchange process has been investigated as a means of trace tritium recovery from a model of the residue from Li17Pb83 *** results indicate that the isotope exchange process is an effective means of tritium recovery from the residue of Li17Pb83 alloy,and the optimum composition of the exchange carrier gas is He + 0.1% *** exchange temperature and number of exchange steps are the main factors influencing the efficiency of tritium recovery from the *** tritium recovery efficiency increases with increasing exchange temperature and number of times of *** recovery efficiency can approach 80% when the residue is treated six times at 823 K.A gas-liquid two-phase contact model to describe the proceeding of tritium release from the liquid Li17Pb83 alloy has been derived on the basis of this experiment.

关键词： Li17Pb83 alloy tritium recovery isotope exchange carrier

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Effects of Processing Parameters on Weld Geometries in Electron Beam Welding Based on Partial Correlation Analysis

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稀有金属材料与工程 2011年第S4期40卷 30-34页

作者： Shen X F,Huang W R,Zhang Y Z Institute of Machinery Manufacturing Technology,China Academy of Engineering Physics,mianyang 621900,China China Acad Engn Phys Inst Machinery Mfg Technol Mianyang 621900 Peoples R China

Accelerating voltage,electron beam current,welding speed constitutes the main electron beam welding process parameters,while the penetration depth and depth-width ratio are two of the most important characteristic parameters of the weld *** complex interactions exists between the five variables,so the analysis of a single process parameter on one of weld geometries is affected by the other process parameters,and the impact of these interference parameters should be excluded to find the real relationship between the variables where partial correlation analysis provides such a *** of the accelerating voltage,electron beam current,welding speed of electron beam welding process parameters on weld geometries is analyzed by using partial correlation *** priority order of adjustment of process parameters is obtained,namely:in order to obtain a larger depth-width ratio indicators,it should be taken firstly to increase the beam current and accelerating voltage,and then to raise the welding speed;in order to obtain greater penetration depth,it is preferred to increase the beam current,followed by increasing the accelerating voltage,and reducing the welding speed finally.

关键词： electron beam welding process parameters characteristic parameters of weld morphology partial correlation analysis

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The Influence of Temperature on the Afterglow Feature of SrAl_2O_4∶Eu,Dy Phosphors

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Journal of Wuhan University of Technology(Materials Science) 2006年第3期21卷 120-122页

作者：王兵 Materials School Southwest University of Science and TechnologyMianyang 621010China

Using a self-designed temperature testing box in which Xenon-lamp irradiation can be applied, the afterglow feature of SrAl2O4： Eu, Dy as a function of temperature has been researched. Two sorts of SrAl2O4 ： Eu, Dy phosphors, namely highest quality commercial one and the self-synthesized one by solid-state reaction process were employed. Results reveal a common phenomenon behaving as phosphorescent sudden extinguishments at a certain low temperature although their threshold temperature value （ about 223 K） has a slight difference . The general charueteristic for the influence of temperature on the afterglow feature presents, compared to the luminescent decay at room temperature （RT）, a bigger and faster decrease of phosphorescent brightness with the reduction of temperature, while decay curves still maitain the same pattern composed of a quick decline part and a platform falling part during which the phosphorescent brightness at 273 K is only aboat 1/2 as big as that at RT, and at 253 K the figure has changed to about 1/3. Finally , the reason of previous observed results has been analyzed briefly in theory.

关键词： afterglow SrAl2O4:Eu,Dy low temperature

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Investigation on oxidation states of rhenium in Re-HEDP

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Nuclear Science and Techniques 2003年第3期14卷 174-177页

作者： WANG Wen-Jin, LUO Shun-Zhong, QIAO Jian, LIU Guo-Ping, LIU Ye-Bing (Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, mianyang 621900) Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics Mianyang 621900

The oxidation states of rhenium in Re-HEDP (hydroxyethylidene diphosphonate) were measured bythe methods of extraction and potentiometric titration. The oxidation state of rhenium in Re-HEDP was mostly +4valence, and the Re(Ⅳ)-HEDP was oxidized to Re( Ⅴ)-HEDP when it was titrated by I3- at pH 2.0. In the reductionsystem of Vc+Sn2+ , ReO4- was only reduced by Sn2+, but Vc was oxidized earlier than Sn2+ when it was titrated by I3.

关键词：铼电势滴定氧化态化合价锡放射性同位素肿瘤治疗

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Feature Extraction of Localized Scattering Centers Using the Modified TLS-Prony Algorithm and Its Applications

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Journal of Systems Engineering and Electronics 2002年第3期13卷 31-39页

作者： Wang Jun Institute of Electronic Engineering, China Academy of Engineering Physics, mianyang 621900, P.R.China Institute of Electronic Engineering China Academy of Engineering Physics Mianyang 621900 P. R. China

This paper presents an all-parametric model of radar target in optic region, in which the localized scattering center's frequency and aspect angle dependent scattering level, distance and azimuth locations are modeled as the feature vectors. And the traditional TLS-Prony algorithm is modified to extract these feature vectors. The analysis of Cramer-Rao bound shows that the modified algorithm not only improves the restriction of high signal-to-noise ratio(SNR)threshold of traditional TLS-Prony algorithm, but also is suitable to the extraction of big damped coefficients and high-resolution estimation of near separation poles. Finally, an illustrative example is presented to verify its practicability in the applications. The experimental results show that the method developed can not only recognize two airplane-like targets with similar shape at low SNR, but also compress the original radar data with high fidelity.

关键词： Localized scattering centers Estimation algorithm Low SNR High resolution.

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Experiments and analysis of gold disk targets irradiated by smoothing beams of Xingguang Ⅱ facilities with 350 nm wavelength

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Science China(Physics,Mechanics & Astronomy) 2007年第6期50卷 716-730页

作者： JIANG ShaoEn,ZHANG BaoHan,LIU ShenYe,YANG JiaMin,SUN KeXu,HUANG TianXuan,DING YongKun & ZHENG ZhiJian National Key Laboratory of Laser Fusion,Laser Fusion Research Center,mianyang 621900,China National Key Laboratory of Laser Fusion Laser Fusion Research Center Mianyang China

Gold disk targets were irradiated using focusing and beam smoothing methods on Xingguang (XG-Ⅱ) laser facilities with 350 nm wavelength,0.6 ns pulse width and 20-80 Joules energies. Laser absorption,light scattering and X-ray conversion were experimentally investigated. The experimental results showed that laser ab-sorption and scattered light were about 90% and 10%,respectively,under focusing irradiation,but the laser absorption increased 5%-10% and the scattered light about 1% under the condition of beam smoothing. Compared with the case of fo-cusing irradiation,the laser absorption was effectively improved and the scattered light remarkably dropped under uniform irradiation; then due to the decrease in laser intensity,X-ray conversion increased. This is highly advantageous to the in-ertial confinement fusion. However,X-ray conversion mechanism basically did not change and X-ray conversion efficiency under beam smoothing and focusing irra-diation was basically the same.

关键词： beam smoothing, lens array, laser absorption, scattered light, X-ray conversion Gold disk targets were irradiated using focusing and beam smoothing methods on Xingguang (XG-II) laser facilities with 350 nm wavelength, 0.6 ns pulse width and 20-80 Joules energies. Laser absorption, light scattering and X-ray conversion were experimentally investigated. The experimental results showed that laser absorption and scattered light were about 90% and 10%, respectively, under focusing irradiation, but the laser absorption increased 5%-10% and the scattered light about 1% under the condition of beam smoothing. Compared with the case of focusing irradiation, the laser absorption was effectively improved and the scattered light remarkably dropped under uniform irradiation then due to the decrease in laser intensity, X-ray conversion increased. This is highly advantageous to the inertial confinement fusion. However, X-ray conversion mechanism basically did not change and X-ray conversion efficiency under beam smoothing and focusing irradiation was basically the same.……

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