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EXPERIMENTAL STUDY ON THE VORTEX FORMATION AND ENTRAINMENT CHARACTERISTICS FOR A ROUND TRANSVERSE JET IN SHALLOW WATER

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Journal of Hydrodynamics 2009年第3期21卷 386-393页

作者： fan jing-yu zhang yan wang dao-zeng shanghai institute of applied mathematics and mechanics Shanghai University Shanghai 200072 China Key Laboratory of Advanced Display and System Applications Ministry of Education and SMIT Center School of Mechatronics Engineering and Automation Shanghai University Shanghai 200072 China

The vortex formation and entrainment characteristics for a round transverse jet in shallow water were experimentally investigated by means of a combination of LIF flow visualization and PIV measurement. A scarf vortex wrapped around the main body of the jet is formed in the near-wall region due to the interaction between the resulting wall jet and sufficiently shallow crossflow, with some more or less unsteady flow properties and with spreading ranges as functions of both the velocity ratio and the water depth within the near field. The entrainment of the ambient crossflow fluid into the jet main body is closely associated with the time-evolving features of the shear layer between the jet and surrounding fluid as well as the induced vortical structures near the wall. In the case of slight impingement upon the wall, the interaction between the jet shear layer and the weak, unstable scarf vortex gives rise to an appreciable local entrainment enhancement, confined in the near-wall region in the vicinity of the stagnation point. While in the case of intense impingement upon the wall, the well-organized and stable scarf vortex gives rise to a greatly enhanced entrainment and a greatly increased lateral spreading rate nearly throughout the overall near field as compared to the conventional wall jet. In addition, the entrainment of the ambient crossflow fluid by the scarf vortex in this case occurs largely on the surface of the unique spiral roller structure by itself due to the presence of smaller and unorganized eddies, and accordingly the scarf vortex is likely to keep its spiral roller structure steadily to a relatively great downstream distance within the near field.

关键词： transverse jet shallow water vortex formation entrainment PIV measurement

LARGE-EDDY SIMULATION OF THREE-DIMENSIONAL VORTICAL STRUCTURES FOR AN IMPINGING TRANSVERSE JET IN THE NEAR REGION

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Journal of Hydrodynamics 2007年第3期19卷 314-321页

作者： fan jing-yu zhang yan wang dao-zeng shanghai institute of applied mathematics and mechanics Shanghai University Shanghai 200072 China Key Laboratory of Advanced Display and System Applications （shanghai university） Ministry of Education and SMIT Center Shanghai University Shanghai 200072 China Department of applied mechanics Chalmers University of Technology SE-412 96 Gothenburg Sweden shanghai institute of applied mathematics and mechanics Shanghai University Shanghai 200072 China

The three-dimensional vortical structures for an impinging transverse jet in the near region were numerically investigated by means of Large-Eddy Simulation （LES）. The LES results reproduced the skewed jet shear layer vortices close to the jet nozzle and the scarf vortex in the near-wall zone in good agreement with the experimental observations. Different vortical modes in the skewed jet shear layer close to the jet nozzle were identified depending upon the velocity ratio between jet and crossflow, namely changing from an approximately axisymmetric mode to a helical one with the velocity ratios varying from 20 to 8. Moreover, the scarf vortex wrapped around the impinging jet in the near-wall zone showed distinct asymmetry with regard to its bilateral spiral legs within the near region. And the entrainment of the ambient crossflow fluids by the scarf vortex in the near-wall zone was appreciably influenced by its asymmetry and in a large part occurred on the surface of the spiral roller structures in the course of spreading downstream.

关键词： Large-Eddy Simulation (LES) impinging jet crossflow vortical structure entrainment

PDA MEASUREMENTS OF TWO-PHASE FLOW STRUCTURE AND PARTICLE DISPERSION FOR A PARTICLE-LADEN JET IN CROSSFLOW

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Journal of Hydrodynamics 2010年第1期22卷 9-18页

作者： fan jing-yu XU Song-li wang dao-zeng shanghai institute of applied mathematics and mechanics Shanghai University Shanghai 200072 China

The two-phase flow structure and particle dispersion for a dilute particle-laden jet in crossflow （JICF） were experimentally investigated by means of Phase Doppler Anemometry （PDA） measurement. The two-phase flow experiments were conducted for different flow conditions and solid particle parameters, including the ratio of the jet velocity to crossflow velocity, the particle size and mass loading. The experimental results indicate that the fine particles with the size of 70 micron and the mass loading of 0.05% have a minor influence on the mean and fluctuation velocity fields of the two-phase JICF. However, the fine particle transport by the two-phase JICF is dominantly and preferentially affected by the shear layer vortices and exhibits a somewhat enhanced dispersion as compared to the fluid. For the coarse particles with the particle size ranging from 300 micron to 700 micron and the mass loading less than 0.16%, the effect of the particle parameters on the fluid phase is associated with both the anisotropic properties of the flow field and the trajectory deviation of the settling particles from the fluid. Compared to the single-phase JICF, the two-phase JICF laden with the coarse particles is recognized to possess more pronounced mean velocity alteration and turbulence modulation of the fluid phase in the presence of the particles with the larger particle size and higher mass loading.

关键词： jet crossflow two-phase flow structure particle dispersion Phase Doppler Anemometry (PDA) measurement

EXPERIMENTAL INVESTIGATIONS ON LONGITUDINAL DISPERSION CHARACTERISTICS OF TIDAL RIVERS

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Journal of Hydrodynamics 2003年第2期15卷 89-94页

作者： fan jing yu, wang dao zeng, Zhong Bao chang shanghai institute of applied mathematics and mechanics, shanghai university, shanghai 200072, china shanghai institute of applied mathematics and mechanics Shanghai University Shanghai 200072 China

The longitudinal dispersion characteristics of tidal rivers areexperimentally investigated in a water channel. The longitudinal dispersion features and influentialfactors on pollutant in various stages of a tidal period in natural rivers are studied; the valueranges and variation trends of the longitudinal dispersion coefficient are obtained by means ofconcentration measurement. The results can provide important parameters for establishing the waterquality mathematical models in tidal rivers.

关键词： tidal river diffusion longitudinal dispersion coefficient

INFLUENCE OF COHERENT STRUCTURE ON SCALAR DIFFUSION IN TURBULENT BOUNDARY LAYERS

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Journal of Hydrodynamics 1999年第4期11卷 99-103页

作者： fan jing yu, wang dao zeng shanghai institute of applied mathematics and mechanics, shanghai university, shanghai 200072, P.R.china shanghai institute of applied mathematics and mechanics Shanghai University Shanghai 200072 P.R.China

Simulation experiments of scalar diffusion have been performed using flow visualisation, quantitative measurement and frequency spectra analysis techniques in an atmospheric boundary layer wind tunnel and in an open tidal water flow channel. The results of experimental research and theoretical analysis indicate that the turbulent intermittent phenomenon plays an important role in scalar diffusion in shear flows. In the near fleld, the scalar diffusion is mainly affected by the nonisotropic quasi periodic large scale coherent structure of turbulence. The rough values of time and space scales of turbulent coherent structure have been obtained by combining flow visualisation with turbulent frequency spectra analysis.

关键词： scalar diffusion coherent structure turbulent boundary layer

Frontiers in high entropy alloys and high entropy functional materials

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Rare Metals 2024年第10期43卷 4639-4776页

作者： Wen-Tao zhang Wen Huang Fu-Jie yu Qi Zhao Xin-Dong Zhu Tao Feng Yao Jiang Xiao-Ming Li Xue-Fei Miao He Zhu Si Lan Xue-Qian wang Bao-Long Shen Zhe Jia Feng-Qi zhang Wei wang Qi Liu yang Ren Xun-Li wang Xiao-Ya Cui Xiao-yang wang Ya-Nan Chen Bing-Bing fan Meng-Ru Li Qi-Long Gao Jia-Ming Guo zeng-Bao Jiao Zhi-Min Guo yu-Ping Zhao Qian yu Rui Huang Ling-Kun zhang Yi-Ping Lu Xu-Bo Li Huai-Jun Lin yan Ma Wei-Ming yang Zhi-Hua Shen Hai-yan He Yong-Gang Sun Yong-Jiang Huang De-Zhuang wang Qing-Feng Liu Fei-yang wang Hui Liu Hong-Hui Wu Li-Qiang wang yang Lu Nan wang Tian-Li wang Wei-Bing Liao Yi-Han wang yuan Wu yu-Zhen Yin Jie Pan Yi zhang Qing wang Jian-yang zhang Tao yang Yasir Sohail Jin-yu zhang Hua Ji Qiang Li Wei-Di Liu Zhi-Gang Chen Xiong-Jun Liu Wen Ma Liang Mao Zhen-Duo Wu School of Materials Science and Engineering Nanjing University of Science and Technology Jiangsu Key Laboratory for Advanced Metallic Materials School of Materials Science and Engineering Southeast University Department of Physics City University of Hong Kong School of Materials Science and Engineering Tianjin University School of Physics and Microelectronics Zhengzhou University Department of Mechanical Engineering Research Institute for Advanced Manufacturing The Hong Kong Polytechnic University Center of Electron Microscopy and State Key Laboratory of Silicon Materials School of Materials Science and Engineering Zhejiang University Key Laboratory of Solidification Control and Digital Preparation Technology (Liaoning Province) School of Materials Science and Engineering Dalian University of Technology institute of Advanced Wear & Corrosion Resistance and Functional Materials Jinan University School of mechanics and Civil Engineering China University of Mining and Technology School of Physical Sciences Great Bay University School of Materials Science andEngineering Harbin Institute of Technology State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Beijing Advanced Innovation Center for Materials Genome Engineering Research Institute for Carbon Neutrality University of Science and Technology Beijing Department of Mechanical Engineering The University of Hong Kong School of Computing Macquarie University Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic Engineering Shenzhen University State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing State Key Laboratory of Materials Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology institute of materials Shanghai University Department of Materials Science and Engineering C

Owing to their exceptional properties, high-entropy alloys(HEAs) and high-entropy materials have emerged as promising research areas and shown diverse applications. Here,the recent advances in the field are comprehensively reviewed,organized into five sections. The first section introduces the background of HEAs, covering their definition, significance,application prospects, basic properties, design principles, and microstructure. The subsequent section focuses on cutting-edge high-entropy structural materials, highlighting developments such as nanostructured alloys, grain boundary engineering,eutectic systems, cryogenic alloys, thin films, micro-nano-lattice structures, additive manufacturing, high entropy metallic glasses, nano-precipitate strengthened alloys, composition modulation, alloy fibers, and refractory systems. In the following section, the emphasis shifts to functional materials, exploring HEAs as catalysts, magneto-caloric materials, corrosion-resistant alloys, radiation-resistant alloys, hydrogen storage systems, and materials for biomedicine. Additionally, the review encompasses functional high-entropy materials outside the realm of alloys, including thermoelectric, quantum dots, nanooxide catalysts, energy storage materials, negative thermal expansion ceramics,and high-entropy wave absorption materials. The paper concludes with an outlook, discussing future directions and potential growth areas in the field. Through this comprehensive review,researchers, engineers, and scientists may gain valuable insights into the recent progress and opportunities for further exploration in the exciting domains of high-entropy alloys and functional materials.

关键词： Cutting-edge structural materials Cutting-edgefunctional materials High entropy alloys

10B-doped MCP detector developed for neutron resonance imaging at Back-n white neutron source

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Nuclear Science and Techniques 2024年第8期35卷 58-68页

作者： Qiang Li Li‑Jiao wang jing‑yu Tang Xiang‑Biao Qiu Zhen Chen Mao‑yuan Zhao Chang‑Jun Ning Kai Pan Wei Xu Tao Li Su‑Peng Lu Han Yi Rui‑Rui fan Chang‑Qing Feng Rong zhang Xiao‑yang Sun Qi An Hao‑fan Bai Jiang‑Bo Bai Jie Bao Ping Cao Qi‑Ping Chen Yong‑Hao Chen zeng‑Qi Cui An‑Chuan fan fan‑Zhen Feng Min‑Hao Gu Chang‑Cai Han Zi‑Jie Han Guo‑Zhu He Yong‑Cheng He yang Hong Yi‑Wei Hu Han‑Xiong Huang Wei Jiang Zhi‑Jie Jiang Zheng‑Yao Jin Ling Kang Bo Li Gong Li Xiao Li yang Li Jie Liu Rong Liu Shu‑Bin Liu Yi‑Na Liu Guang‑yuan Luan Jie Ren Zhi‑Zhou Ren Xi‑Chao Ruan Zhao‑Hui Song Kang Sun Zhi‑Xin Tan Sheng‑Da Tang Jin‑Cheng wang Peng‑Cheng wang Zhao‑Hui wang Zhong‑Wei Wen Xiao‑Guang Wu Xuan Wu Cong Xia Yong‑Ji yu Guo‑Hui zhang Hang‑Chang zhang Lin‑Hao zhang Qi‑Wei zhang Xian‑Peng zhang yu‑Liang zhang yue zhang Zhi‑Yong zhang Zhi‑Hao Zhou Ke‑Jun Zhu Chong Zou institute of High Energy Physics Chinese Academy of Sciences(CAS)Beijing 100049China Spallation Neutron Source Science Center Dongguan 523803China State Key Laboratory of Particle Detection and Electronics Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Dongguan Songshan Lake Future School Dongguan 523808China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230027China State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China North Night Vision Science and Technology(Nanjing)Research institute Co.Ltd Nanjing 211106China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China institute of Modern Physics Fudan UniversityShanghai 200433China Key Laboratory of Nuclear Data China Institute of Atomic EnergyBeijing 102413China china Academy of Engineering Physics Institute of Nuclear Physics and ChemistryMianyang 621900China USTC archaeometry lab University of Science and Technology of ChinaHefei 230026China Northwest institute of Nuclear Technology Xi’an 710024China university of Chinese Academy of Sciences Beijing 100049China china Shipbuilding Trading Co. LtdBeijing 100044China

Neutron resonance imaging(NRI)has recently emerged as an appealing technique for neutron *** complexity surpasses that of conventional transmission imaging,as it requires a high demand for both a neutron source and ***,the progression of NRI technology has been sluggish since its inception in the 1980s,particularly considering the limited studies analyzing the neutron energy range above *** white neutron source(Back-n)at the china Spallation Neutron Source(CSNS)provides favorable beam conditions for the development of the NRI technique over a wide neutron energy range from eV to ***-sensitive microchannel plates(MCP)have emerged as a cutting-edge tool in the field of neutron detection owing to their high temporal and spatial resolutions,high detection efficiency,and low *** this study,we report the development of a 10B-doped MCP detector,along with its associated electronics,data processing system,and NRI experiments at the *** heavy elements such as gold,silver,tungsten,and indium can be easily identified in the transmission images by their characteristic resonance peaks in the 1–100 eV energy range;the more difficult medium-weight elements such as iron,copper,and aluminum with resonance peaks in the 1–100 keV energy range can also be *** particular,results in the neutron energy range of dozens of keV(Aluminum)are reported here for the first time.

关键词： Neutron resonance imaging 10B doped MCP detector White neutron source Sample nuclide identification

Experimental study on the effects of sediment size and porosity on contaminant adsorption/desorption and interfacial diffusion characteristics

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Journal of Hydrodynamics 2013年第1期25卷 20-26页

作者： fan jing-yu HE Xiao-yan wang dao-zeng shanghai institute of applied mathematics and mechanics Shanghai University

The joint effects of the sediment size and porosity on the contaminant adsorption/desorption and interfacial diffusion characteristics were experimentally investigated. The adsorption of Phosphorus （P） on the natural and artificial sediment suspensions was measured with respect to the P adsorption isotherms and kinetics in the experiment. The obtained adsorption isotherms for different grain-sized sediment suspensions fit well with the Langmuir equation, dependent on the initial aqueous concentration and sediment content. The P kinetic adsorption behaviors for cohesive fine-grained and non-cohesive coarse-grained sediment suspensions clearly show the size-dependent feature. On the other hand, the P kinetic release feature of a porous sediment layer is affected by not only the direct desorption of the uppermost sediments, but also the diffusivity in the pore-water within the underlying sediment layer, characterized by the sediment size and porosity, respectively. Furthermore, the temporal contaminant release from the permeable sediment layer into the overlying water column increases with the increasing flow velocity, while this enhancement in mediating the interfacial diffusion flux is somewhat insignificant in an immediate release stage, largely due to the resistance of the diffusive boundary layer on the hydrodynamic disturbance.

关键词： sediment contaminant adsorption desorption interfacial diffusion

Experimental investigation on diffusive contaminant release from permeable sediment layer under unidirectional unsteady flow

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Journal of Hydrodynamics 2014年第6期26卷 965-970页

作者：樊靖郁王道增 shanghai institute of applied mathematics and mechanics Shanghai University

The interfacial diffusive contaminant（phosphorus） release from permeable sediment layer into overlying water column under a unidirectional unsteady（periodic） flow condition was experimentally measured and analyzed. The experimental results indicate that the gross diffusive contaminant release rate is substantially enhanced as compared to that under a steady flow condition, and this enhancement trend is much more pronounced in an immediate release stage. The interfacial diffusive contaminant release rate tends to increase with the increasing flow velocity, decreasing period and augmenting amplitude for the case of the unsteady flow. The additional interfacial diffusive contaminant release under the unsteady flow condition may be related to the hydrodynamic response of the diffusive boundary layer to the flow unsteadiness of the overlying water, depending upon not only the periodic thickness variation of the diffusive boundary layer immediately above the sediment-water interface modulated by the temporal flow velocity of the overlying water column but also the intensified turbulent mixing between the overlying water and the pore-water within the superficial sediment layer induced by an alternate acceleration/deceleration fluctuation during each period.

关键词： unsteady flow contaminant sediment diffusive release sediment-water interface