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meso-scale available gravitational potential energy in the world oceans

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Acta Oceanologica Sinica 2006年第5期25卷 1-13页

作者： FENG Yang WANG Wei HUANG Ruixin Physical Oceanography Laboraltory Ocean University of China Qingdao 266003 China Department of Physical Oceanography Woods Hole Oceanographic Institution Woods Hole MA 02543 USA

The pitfalls of applying the commonly used definition of available gravitational potential energy （AGPE） to the world oceans are re-examined. It is proposed that such definition should apply to the meso-scale problems in the oceans, not the global scale. Based on WOA98 climatological data, the meso-scale AGPE in the world oceans is estimated. Unlike previous results by Oort et al. , the meso-scale AGPE is large wherever there is a strong horizontal density gradient. The distribution of meso-scale AGPE reveals the close connection between the baroclinic instability and the release of gravitational potential energy stored within the scale of Rossby deformation radius.

关键词： energy of ocean circulation available potential gravitational energy meso-scale baroclinic instability Rossby deformation radius

meso-scale circulation at the intermediate-depth east of Mindanao observed by Argo profiling floats

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Science China Earth Sciences 2010年第3期53卷 432-440页

作者： ZHOU Hui1, YUAN DongLiang1, GUO PeiFang2, SHI MaoChong2 & ZHANG QiLong 1 Key Laboratory of Ocean Circulation and Wave Studies, Chinese Academy of Sciences, Qingdao 266071, China 2 Physical Oceanography Laboratory, Ocean University of China, Qingdao 266100, China Key Laboratory of Ocean Circulation and Wave Studies Chinese Academy of Sciences Qingdao China Physical Oceanography Laboratory Ocean University of China Qingdao China

The meso-scale circulation at the intermediate depth east of Mindanao is studied using Argo profiling floats observations. The trajectories and the parking-depth velocities of Argo floats show that the intermediate-depth circulation east of Mindanao contains significant meso-scale features that are highly variable both in space and in time. Both cyclonic and anticyclonic eddies at the intermediate depth (1000–2000 m) are indicated by the trajectories east of Mindanao. The mean tangential velocities of these eddies are about 10 cm/s at 2000 m and over 20 cm/s at 1000 m, which indicates that the geostrophic calculation may contain large errors due to the vigorous eddy activity at the reference levels. The analyses also suggest that these eddies might play an important role in mass and vorticity balances of the intermediate-depth circulation east of Mindanao.

关键词： Mindanao Current intermediate-depth circulation meso-scale eddy Argo profiling float

Propagation of shock waves in dry and wet sandstone:Experimental observations,theoretical analysis and meso-scale modeling

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Defence Technology（防务技术） 2018年第5期14卷 513-521页

作者： Chuang Liu Yang Wu Xian-feng Zhang Jia-jie Deng Chen-yang Xu Wei Xiong Meng-ting Tan School of Mechanical Engineering Nanjing University of Science and TechnologyNanjingXiaolingwei 200NanjingChina NO.208 Reseach Institute of China Ordnance Industries BeijingChina

Methods of experimental observations, theoretical analysis and meso-scale modeling were used to study the propagation processes of shock waves in dry and wet sandstone under dynamic impact in this *** to the results from the dynamic impact experiments with velocity of 0.2-0.5 km/s, it was found that the velocity of shock wave increases linearly with water content. Additionally, the velocity of the shock wave in the sandstone showed a linearly increased regularity with the increasement of the impact velocity, which was proved by theory in this paper. Furthermore, meso-scale simulation models were performed and the simulation results showed that sandstone's porosity reduced the shock waves velocity compared to nonporous materials. Pore space filled with water counteracts the effects of porosity, resulted in larger shock wave velocity.

关键词： Dynamic impact Shock wave meso-scale simulation Sandstone

MODELING OF meso-scale STRUCTURES IN PARTICLE-FLUID SYSTEMS: THE EMMS/CFD APPROACH

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China Particuology 2005年第1期3卷 78-79页

作者： NingYang WeiWang WeiGe JinghaiLi Multi-PhaseReactionLaboratory InstituteofProcessEngineeringChineseAcademyofSciencesBeijing100080P.R.China

meso-scale structures existing in the form of particle-rich clusters, streamers or strands in circulating fluidized beds, and of ascending bubble plumes and descending liquid-rich vortices in bubble columns and slurry-bed reactors, as commonly observed, have played an important role in the macro-scale behavior of particle-fluid systems. These meso-scale structures span a wide range of length and time scales, and their origin, evolution and influence are still far from being well understood.

关键词： meso-scale computational fluid dynamics particle-fiuid system fluidization multi-scale

MODELING OF meso-scale STRUCTURES IN PARTICLE-FLUID SYSTEMS: THE EMMS/CFD APPROACH

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Particuology 2005年第Z1期 78-79页

作者： Ning Yang, Wei Wang, Wei Ge and Jinghai Li Multi-Phase Reaction Laboratory, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100080, P. R. China

关键词： meso-scale computational fluid dynamics particle-fiuid system fluidization multi-scale

Design of Web System for meso-scale Meteorological Observational Station Based on SVG

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Meteorological and Environmental Research 2010年第1期1卷 39-41,45页

作者：陈斌钱毅吕刚华连生吴奇生安徽省大气探测技术保障中心安徽合肥230031 电子科技大学通信与信息工程学院四川成都610054

The web of meso-scale meteorological observational station based on WebGIS realized by SVG technology was briefly *** grasping and applying SVG technology,the high-density automatic observational station in Anhui Province was *** web of meso-scale meteorological observational stations constructed by SVG technique can display the network graphics of weather data and intuitionistic vector graphics interface.

关键词： SVG XML WebGIS Vector graphics meso-scale China

mesoscopic investigation on seismic performance of corroded reinforced concrete columns

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Earthquake Engineering and Engineering Vibration 2022年第4期21卷 969-985页

作者： Jin Liu Li Yanxi Zhang Renbo Du Xiuli Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100024China

In addition to the normal service loadings,engineering structures may be subjected to occasional loadings such as earthquakes,which may cause severe *** the steel rebar is corroded,the damage could be more *** investigate the seismic performance of corroded RC columns,a three-dimensional mesoscale finite element model was *** this approach,concrete was considered as a three-phase composite composed of aggregate,mortar matrix and interfacial transition zone(ITZ).The nonlinear spring were used to describe the bond slip between steel and *** degradation of the material properties of the steel rebar and cover concrete as well as the bonding performance due to corrosion were taken into *** rationality of the developed numerical analysis model was verified by the good agreement between the numerical results and the available experimental *** this basis,the effect of corrosion level,axial force ratio and shear-span ratio on the seismic performance of corroded RC columns,including lateral bearing capacity,ductility,and energy consumption,were explored and *** simulation results indicate that the mesoscopic method can consider the heterogeneity of concrete,to more realistically and reasonably reflect the destruction process of structures.

关键词： reinforcement corrosion reinforced concrete column meso-scale finite element analysis seismic behavior

CFD simulation of the effects of a suspension section on the hydrodynamics of a circulating fluidized bed

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Particuology 2019年第2期17卷 1-8页

作者： Cenfan Liu Nan Zhang Wei Wang State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China China Special Equipment Inspection and Research Institute Beijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China

Gas-solid two-phase flow in a circulating fluidized bed (CFB) is affected by operating conditions (e.g., superficial gas velocity, solids inventory), material properties and geometric factors, such as the entry and exit configuration. In particular, the suspension section, which is located between the riser bottom and the solids recycle inlet, affects the hydrodynamics in the riser significantly. However, the suspension section has received less attention compared with other geometric factors. Most computational fluid dynamics (CFD) simulations, especially two-dimensional simulations do not take this factor into account. We performed three-dimensional, full-loop CFD simulations with a drag coefficient that was determined by the energy-minimization multi-scale model, and investigated the flow behavior of two CFBs with different suspension-section lengths. The simulation resuits revealed that the axial profiles of voidage in the riser with a longer suspension section are more likely S-shaped, whereas those with shorter suspension sections decay exponentially. The dependences of solids flux on solids inventory differ in the two CFBs. A shorter suspension section may result in a smooth transition from dilute to dense transport without intermediate accumulative choki-ng, whereas a Ion ger suspe nsion section may lead to a choking transition. These simulation results are qualitatively consistent with the flow behaviors described in literature.

关键词： Computational fluid dynamics Fluidization meso-scale Energy-minimization multi-scale Suspension section

Summary of current research on Central Asian vortex

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Advances in Climate Change Research 2017年第1期8卷 3-11页

作者： YANG Lian-Mei ZHANG Yun-Hui Institute of Desert Meteorology China Meteorological Administration Urumqi 830002 China Central Asia Center for Atmospheric Science Research Urumqi 830002 China Xinjiang Meteorological Observation Urumqi 830002 China

The Central Asian vortex (CAV) is an important synoptic-scale system that causes rainstorms, short-term heavy precipitation, hail, and sustained low temperatures in Xinjiang. This paper summarizes the current research conducted on the CAV since the 1960s. The objective definition of the CAV has been revised and a deep and shallow CAV classification proposed. Two high-frequency areas of deep CAVactivity are the Kazakhstan hills (Sayan mountains) and the eastern area of the Aral Sea (Tashkent); events mostly occur in summer and 40% cause strong rainfall. In addition, two high-frequency activity areas of the shallow CAV are located in the west and south of the Pamirs Plateau and mostly occur in spring; 23.2% of occurrences cause strong rainfall. The western and eastern water vapor transport relates to westerlies and a strong lowlevel easterly jet stream (LLEJ) extending from Gansu to Xinjiang, respectively, and water vapor over the Tibetan Plateau transports even more northwards and enters Xinjiang. The deep CAV has an obvious cold core structure down to 300 hPa. The conversion terms from eddy available potential energy eAET to eddy kinetic energy eKET and eddy kinetic energy inflow eBKET from the open atmospheric region boundaries are the main sources of KE which cause rapid development of the CAV. The anomalous anti-cyclone center over the northeast Atlantic is the fountain of Rossby wave energy dispersion; Rossby waves propagate from the northeast Atlantic to eastern Europe (Urals (EEU)), and then continuously propagate to Central Asia causing development of the CAV. The CAV requires further study to characterize the meso-scale system structure and evolution characteristics. In addition, physical modeling of the severe convective weather occurring under the CAV is required to determine the critical impacts of this severe convective weather and enable forecasting and early-warning indexes.

关键词： Central Asian vortex Circulation configuration Energy propagation meso-scale system