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A Dip Structure in the Intrinsic Toroidal Rotation Near the Edge of the Ohmic Plasmas in EAST

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Plasma Science and Technology 2011年第4期13卷 397-404页

作者：徐国盛 V.NAULIN 万宝年郭后扬张炜常加峰颜宁丁斯晔张凌王亮刘少承刘鹏蒋敏汪惠乾 J.Juul RASMUSSEN A.H.NIELSEN 肖持进高翔胡立群朱思铮吴振伟钱金平龚先祖 Institute of Plasma Physics Chinese Academy of Sciences Association Euratom-Risφ DTU tri alpha energy Rancho Santa Margarita Plasma Physics Laboratory University of SaskatchewanSaskatoonSK S7N 5E2Canada

Ion＇s toroidal velocity, vt, in both the outermost 4 cm of the confined region and the scrap-off layer of Ohmic L-mode plasmas in EAST was measured using Mach probes. At about 1 cm inside the separatrix a local minimum in vt was observed, from which a cocurrent rotation increased both inwards and outwards. The radial width of the vt dip was 1 cm to 2 cm, and both the density and electron temperature profiles exhibited steep gradients at this dip position. It was observed in both divertor and limiter configurations. To find out its origin, the toroidal torques induced by neutral friction, neoclassical viscosity, collisional perpendicular shear viscosity, ion orbit loss and turbulent Reynolds stress were estimated using the measured parameters. Our results indicate that in this particular parameter regime the neutral friction was the dominant damping force. The calculated cocurrent toroidal torque by the neoclassical viscosity dominates over those from the collisional perpendicular shear viscosity, ion orbit loss and turbulent Reynolds stress. These results are potentially important for the understanding of boundary conditions for the intrinsic toroidal momentum in tokamak plasmas.

关键词： intrinsic rotation turbulent Reynolds stress toroidal torques neutral friction

A Code that Simulates Fast-Ion Dα and Neutral Particle Measurements

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Communications in Computational Physics 2011年第8期10卷 716-741页

作者： W.W.Heidbrink D.Liu Y.Luo E.Ruskov B.Geiger Department of Physics and Astronomy University of CaliforniaIrvineCaliforniaCA 92697USA Max-Planck Institute fur Plasmaphysik GarchingGermany Department of Physics University of Wisconsin-MadisonMadisonWI 53706USA tri alpha energy corporation 27211 BurbankFoothill RanchCA 92610USA

A code that models signals produced by charge-exchange reactions between fast ions and injected neutral beams in tokamak plasmas is *** the fastion distribution function as input,the code predicts the efflux to a neutral particle analyzer(NPA)diagnostic and the photon radiance of Balmer-alpha light to a fastion Dα(FIDA)*** with both the primary injected neutrals and with the cloud of secondary"halo"neutrals that surround the beam are *** calculation of the fraction of neutrals that occupy excited atomic states(the collisionalradiative transition equations)is an important element of the *** with TRANSP output and other tests verify the *** selection of grid size and other parameters facilitate efficient *** output of the code has been validated by FIDA measurements on DIII-D but further tests are warranted.

关键词： Fast ions

Radiative Divertor Plasma Behavior in L- and H-Mode Discharges with Argon Injection in EAST

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Plasma Science and Technology 2013年第7期15卷 614-618页

作者：王东升郭后扬尚毅梓甘开福汪惠乾陈颖杰刘少承王亮高伟向玲燕吴振伟罗广南 the EAST team Department of Modern Physics University of Science and Technology of China Institute of Plasma Physics Chinese Academy of Sciences tri alpha energy Inc.Rancho Santa Margarita CA 92688-7010 USA School of Engineering and Applied Science Harvard University

Introducing strong radiative impurities as an important way to mitigate the peak heat load will be employed in EAST for high power long pulse experiments were explored under both low （L） and the first time in EAST, with the injection of argon into divertor plasmas has been considered at the divertor target plate for ITER, and operations. To this end, radiative divertor high （H） - mode confinement regimes, for and its mixture （25% Ar in D2）. The Ar injection greatly reduced particle and heat fluxes to the divertor in L-mode discharges, achieving nearly complete detached divertor plasma regimes for both single null （SN） and double null （DN） configurations, without increasing the core impurity content. In particular, the peak heat flux was reduced by a factor of ~6~ significantly reducing the intrinsic in-out divertor asymmetry for DN, as seen by both the new infra-red camera and the Langmuir probes at the divertor target. Promising results have also been obtained in the H-modes with argon seeding, demonstrating a significant increase in the frequency and decrease in the amplitude of the edge localized modes （ELMs）, thus reducing both particle and heat loads caused by the ELMs. This will be further explored in the next experimental campaign with increasing heating power for long pulse operations.

关键词： radiative divertor impurity heat flux single null double null

Formation of RF Plasma Transport Channel in External B-Field

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Journal of energy and Power Engineering 2012年第5期6卷 725-729页

作者： Ping Feng Vitaly Bystritskii Ivan Isakov Vasily Matvienko Kurt Walters Department of Physics & Astronomy University of California Irvine California 92697 USA tri alpha energy lnc Foothill Ranch California 92610 USA Institute of High Voltage Technology Tomsk 63050 Russia Institute of Nuclear Physics Tomsk 63050 Russia

The paper describes experiments on formation of a plasma channel with imbedded B-field for transporting high power ion beam. The plasma was generated with a 5-turn loop inductive antenna driven by an H-bridge type RF generator. The azimuthal B-field in the channel of 0.5-1.5 kG was formed by a pulsed current from external capacitor bank. Control of the hydrogen gas pressure was provided by an electromagnetic puffvalve. The paper describes experimental devices and results on the generated plasma parameters as function of RF frequency, antenna voltage, pulse duration and puffgas pressure. When operating at-1 kG B-field, ambient gas pressure in the range of few -10 mTorr, and 5 kV antenna voltage at resonant frequency of 150 kHz, the plasma density range was （3-7）×10^12 cm3 with a temperature of a few eV.

关键词： Plasma RF B-field ion beam high power ion beam.

An experimental method to obtain the hard alpha anomaly distribution for titanium alloy aeroengine disks

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Chinese Journal of Aeronautics 2021年第4期34卷 67-82页

作者： Shuiting DING Huimin ZHOU Bochao PAN Haibin JI Xiaojun GUO Guo LI Aircraft/Engine Integrated System Safety Beijing Key Laboratory School of Energy and Power EngineeringBeihang UniversityBeijing 100083China Institute of Metal Research Chinese Academy of SciencesShenyang 110004China Aero Engine corporation of China(AECC) Hunan Aviation Powerplant Research InstituteZhuzhou 412000China

A probability-based damage tolerance methodology has been proposed to improve the recognition of material anomalies, especially hard alpha(TiN) anomalies for aeroengine rotor disks. A key input to this method is hard alpha anomaly distribution, which reflects the occurrence rate and size of anomalies present in the finished part material of titanium rotors. Since anomalies rarely occur naturally, an experimental method is proposed to obtain the anomaly distribution for titanium alloy aeroengine disks to reflect and equivalently replace the manufacturing development in titanium industry. In general, the anomaly distribution information can be divided into two parts: the Probability of Detection(POD) curve and the detected anomaly distribution, which contains the size and frequency data of the detected anomalies. The distribution can be established based on several appropriate assumptions and derivation steps with different confidence levels of POD curves and detected anomaly distributions. In this case, the distribution can be obtained in a relatively short time as a key input to the probability-based damage tolerance methodology. Then the Probability of Failure(POF) can be calculated, and the value is found to vary with different confidence levels. On this basis, the conservative estimated POF can be obtained in conjunction with confidence levels.

关键词： Aeroengine disk Artificial preparation Hard alpha anomaly distribution Probability of detection(POD) Probability risk assessment

Creep Behavior of Fusion Zone and Base Metal of the Electron Beam Weldments of a Near-alpha Titanium Alloy

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Journal of Materials Science & Technology 2010年第6期26卷 564-571页

作者： Zhiyong Chen Jinwei Li Jie Liu Qingjiang Wang Jianrong Liu Rui Fang Division of Titanium alloys Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Research Department of High energy Density Beam Processing Technology Beijing Aeronautical Manufacturing Technology Research Institute Beijing 100024 China AVIC Shenyang Liming Aero-engine (Group) corporation LTD Shenyang 110043 China

The high temperature creep behavior of fusion zone （FZ） and of a near-alpha titanium alloy Ti-60 has been investigated. base metal （BM） of the electron beam weldments While the BM shows a fully transformed, coarse primary β grains with large colonies consisting of aligned α lamellar, the FZ exhibits thin martensitic α′ platelets in the columnar β grains. The creep results show that the steady state creep rates of FZ follow the power-law creep, with the stress exponents obtained in the range from 5.6 （550℃） to 5.9 （600℃）, and corrected activation energies of 309-352 kJ/mol; the stress exponents of BM exhibit different values when the creep testing stress and temperature alternate. The values of 2.4-3.2 are obtained when the stresses are under 220 MPa or the temperature is 550℃, also an exponent of 6.6 is achieved at stresses above 220 MPa at 600℃. The corrected activation energies of BM corresponding to the stress exponents are 123-161 kJ/mol （n=2.4-3.2） and 344 kJ/mol （n=6.6）. The creep mechanisms of FZ and BM have been discussed in light of the creep microstructures, activation energies and the stress exponents. The creep mechanisms of FZ is the diffusion controlled dislocation climb, the creep of BM is controlled by ＇solute drag＇ creep and dislocation climb when the stress and temperature are different. Transmission electron microscopy （TEM） observations of the dislocation structures of crept specimens are presented to give some supports for the creep behavior of FZ and BM. In addition to the creep mechanism of dislocation movement, the interface sliding has been found to play an important role during creep of FZ.

关键词： Steady state creep Stress exponent Activation energy Electron beam welding Near-alpha titanium alloy

Study on Technology Clusters for Direct Utilization of CO2-Rich Natural Gas and Construction of Hybrid System for energy and Chemicals Production

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China Petroleum Processing & Petrochemical Technology 2020年第2期22卷 1-9页

作者： Wu Qing Department of Science and Technology Development China National Offshore Oil CorporationBeijing 100010

Based on industrial production with an annual capacity of million tons of methanol,ammonia/urea,etc.,a platform technology is developed for direct,green,efficient,and high-value mega-size utilization of the CO2-rich nature gas,which is the technology of CO2-rich natural gas dry reforming and hydrogen *** following technologies are discussed,such as CO2-rich natural gas dry reforming integrated with the Fischer-Tropsch synthesis to olefins(FTO)technology for producing high value-added linear alpha olefins(LAO);CO2-rich natural gas dry reforming integrated with low carbon olefin linear hydroformylation technology to produce higher carbon alcohols;direct methanol production from CO2 and hydrogen;and the new cutting edge technology of photo-catalytic *** addition,simple techno-economic evaluations of two technologies mentioned above are *** CO2-rich natural gas dry reforming integrated with FTO technology can achieve about 30%of internal rate return(IRR),while the low carbon olefin linear hydroformylation technology could have a static payback period of 2.57 years when the capacity of 2-propylhexanol(2-PH)reaches 100 kt/*** on the mega-size green and high-efficient CO2-rich natural gas direct utilization technology,a hybrid energy and chemical production system framework with good prospects is preliminarily designed.A modern industry zone with an annual capacity of more than 10 Mt of CO2 converted to high value-added products is underway.

关键词： CO2-riched natural gas dry reforming Fischer-Tropsch to olefins Fischer-Tropsch to aromatics linear hydroformylation techno-economic evaluation

Dynamic Comprehensive Assessment of Power Development Based on Provincial Data

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CSEE Journal of Power and energy Systems 2020年第3期6卷 672-680页

作者： Wei Hu Qiuting Guo Yifan Zhou Yi Kang Huanshuai Bing Dan Bao State Key Lab of Power Systems the Department of Electrical EngineeringTsinghua UniversityBeijing 100084China Central Southern China Electric Power Design Institute China Power Engineering Consulting Group CorporationWuhan 430071China Northeast Branch State Grid Corporation of ChinaShenyang 110180China

Dynamic comprehensive assessment of regional power industry development levels is of paramount importance for understanding the development characteristics and potential of the local power industry.A tri-level evaluation index system is established,describing five aspects of the local power industry development level,specifically,the coordination degree between the power industry and economy/energy,power generation,power consumption,power supply and development potential.A combination of information entropy and the analytic hierarchy process(AHP)is used to establish a static evaluation model,and a blend of subjective opinions and objective data information is then *** aggregating the static evaluation model for each time period based on a time-ordered weighting vector calculated using time-ordered information entropy,a dynamic comprehensive evaluation model of power industry development level is *** considering provincial data from China recorded during 2007 to 2016 as the sample set,through synchronic and diachronic comparisons of the evaluation results,the differences,characteristics and potential of local power industry development in China are explored.

关键词： Analytic hierarchy process development level of power electric industry dynamic comprehensive assessment information entropy

Coating of Fe, Ni on α-alumina microspheres by heterogeneous precipitation

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Journal of Central South University of Technology 2006年第1期13卷 22-26页

作者：沈湘黔李东红景茂祥李旺兴 School of Materials Science and Engineering Jiangsu University Zhenjiang 212013 China School of Materials Science and Engineering Jiangsu University Zhenjiang 212013 ChinaZhengzhou Research Institute China Aluminum Corporation Zhengzhou 450041 China Zhengzhou Research Institute China Aluminum Corporation Zhengzhou 450041 China

The precursors with NiCO3·2Ni（OH）2·2H2O, Fe2O3·nH2O coated alumina microspheres were prepared by the aqueous heterogeneous precipitation using metal salts, ammonium bicarbonate and α-Al2O3 micropowders as the starting materials. Magnetic metal Ni, α-Fe coated alumina, core-shell structural microspheres were successfully obtained by thermal reduction of the precursors at 700℃ for 2h, respectively. Powders of the precursors and the resultant metal （Ni, α-Fe） coated alumina micropowders were characterized by scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction. The results show that optimized precipitation parameters are concentration of alumina micropowders of 15g/L, rate of adding reactants of 5mL/min and pH value of 7.5. And under the optimized conditions, the spherical precursors without aggregations or agglomerations are obtained, then transferred into Ni, α-Fe coated alumina microspheres by thermal reduction. It is possible to adjust metal coating thicknesses and fabricate a multilayer structured metal/ceramics, core-shell microspherical powder materials.

关键词： heterogeneous precipitation metal-coated alumina microsphere Ni α-Fe