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Design of Web System for Meso-scale Meteorological Observational Station Based on SVG
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作者 陈斌 钱毅 +2 位作者 吕刚 华连生 吴奇生 《Meteorological and Environmental Research》 CAS 2010年第1期39-41,45,共4页
The web of meso-scale meteorological observational station based on WebGIS realized by SVG technology was briefly introduced.Through grasping and applying SVG technology,the high-density automatic observational statio... The web of meso-scale meteorological observational station based on WebGIS realized by SVG technology was briefly introduced.Through grasping and applying SVG technology,the high-density automatic observational station in Anhui Province was developed.The web of meso-scale meteorological observational stations constructed by SVG technique can display the network graphics of weather data and intuitionistic vector graphics interface. 展开更多
关键词 SVG XML WEBGIS Vector graphics meso-scale China
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The Impact of Meso-Scale Eddies on the Subtropical Mode Water in the Western North Pacific 被引量:6
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作者 LIU Cong LI Peiliang 《Journal of Ocean University of China》 SCIE CAS 2013年第2期230-236,共7页
Based on the temperature and salinity from the Argo profiling floats and altimeter-derived geostrophic velocity anomaly (GVA) data in the western North Pacific during 2002-2011, the North Pacific Subtropical Mode Wate... Based on the temperature and salinity from the Argo profiling floats and altimeter-derived geostrophic velocity anomaly (GVA) data in the western North Pacific during 2002-2011, the North Pacific Subtropical Mode Water (NPSTMW) distribution is investigated and cyclonic and anti-cyclonic eddies (CEs and AEs) are constructed to study the influence of their vertical structures on maintaining NPSTMW. Combining eddies identified by the GVA data and Argo profiling float data, it is found that the average NPSTMW thickness of AEs is about 60 dbar, which is thicker than that of CEs. The NPSTMW thicker than 150 dbar in AEs accounts for 18%, whereas that in CEs accounts for only 1%. About 3377 (3517) profiles, which located within one diameter of the nearest CEs (AEs) are used to construct the CE (AE). The composite AE traps low-PV water in the center and with a convex shape in the vertical section. The 'trapped depth' of the composite CE (AE) is 300 m (550 m) where the rotational velocity exceeds the transitional velocity. The present study suggests that the anticyclonic eddies are not only likely to form larger amounts of NPSTMW, but also trap more NPSTMW than cyclonic eddies. 展开更多
关键词 thickness ofNPSTMW meso-scale eddies swirl velocity trapped depth
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Meso-scale modeling of chloride diffusion in concrete with consideration of effects of time and temperature 被引量:4
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作者 Li-cheng WANG Tamon UEDA 《Water Science and Engineering》 EI CAS 2009年第3期58-70,共13页
A meso-scale truss network model was developed to predict chloride diffusion in concrete. The model regards concrete as a three-phase composite of mortar matrix, coarse aggregates, and the interfacial transition zone ... A meso-scale truss network model was developed to predict chloride diffusion in concrete. The model regards concrete as a three-phase composite of mortar matrix, coarse aggregates, and the interfacial transition zone (ITZ) between the mortar matrix and the aggregates. The diffusion coefficient of chloride in the mortar and the ITZ can be analytically determined with only the water-to-cement ratio and volume fraction of fine aggregates. Fick's second law of diffusion was used as the governing equation for chloride diffusion in a homogenous medium (e.g., mortar); it was discretized and applied to the truss network model. The solution procedure of the truss network model based on the diffusion law and the meso-scale composite structure of concrete is outlined. Additionally, the dependence of the diffusion coefficient of chloride in the mortar and the ITZ on exposure duration and temperature is taken into account to illustrate their effect on chloride diffusion coefficient. The numerical results show that the exposure duration and environmental temperature play important roles in the diffusion rate of chloride ions in concrete. It is also concluded that the meso-scale truss network model can be applied to chloride transport analysis of damaged (or cracked) concrete. 展开更多
关键词 meso-scale modeling CONCRETE chloride diffusion truss network model
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Flame Imaging in Meso-scale Porous Media Burner Using Electrical Capacitance Tomography 被引量:5
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作者 陈琪 刘石 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第2期329-336,共8页
This study was conducted to investigate the characteristics of meso-scale combustion.The technique of electrical capacitance tomography(ECT) was used to locate flame position and monitor the effect corresponding to va... This study was conducted to investigate the characteristics of meso-scale combustion.The technique of electrical capacitance tomography(ECT) was used to locate flame position and monitor the effect corresponding to varied air/fuel ratio in a meso-scale combustor.Combustion phenomena including igniting,quenching and unsteady combustion have been visualized using ECT.The method of metallization protecting ECT sensor from high temperature damage and the novel calibration method adapted to ECT monitoring of unknown permittivity flame have been shown to be successful.At the same time,electrical nature of combustion and dielectric characteristics of hy-drocarbon flame were studied.The relationship between flame permittivity and state parameters of combustion gas was demonstrated preliminarily. 展开更多
关键词 electr:ical capacitance tomography meso-scale burner COMBUSTION flame permittivity
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Meso-scale available gravitational potential energy in the world oceans 被引量:2
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作者 FENG Yang WANG Wei HUANG Ruixin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第5期1-13,共13页
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 proble... 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. 展开更多
关键词 energy of ocean circulation available potential gravitational energy meso-scale baroclinic instability Rossby deformation radius
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Analysis on the Meso-scale System Activity and the Structure Characteristics of A Short-time Rainstorm 被引量:3
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作者 黄卓禹 刘志雄 +2 位作者 肖妙妮 沈安云 吴艳林 《Meteorological and Environmental Research》 CAS 2010年第9期57-61,66,共6页
By using the rainfall data in the regional automatic station,FY-2E satellite data,NCEP reanalysis data,the evolution features and the structure characteristics of a meso-scale convective system(MCS) which happened on ... By using the rainfall data in the regional automatic station,FY-2E satellite data,NCEP reanalysis data,the evolution features and the structure characteristics of a meso-scale convective system(MCS) which happened on May 6 in 2010 in Loudi City of Hunan Province were analyzed.The results showed that MCS was the important influence system for the generation and development of strong precipitation.The equivalent blackbody brightness temperature(TBB) field of satellite inversion could directly reflect the convective activity of cumulus,the precipitation distribution and the intensity characteristics in the rainstorm process.TBB low value belt had the good corresponding relationship with the rainstorm falling zone.The disturbance flow field and the height field which passed Barnes band-pass wave filtering represented that there existed the obvious high-layer anticyclonic circulation and the low-layer cyclonic circulation near the rainstorm zone.The divergence in the high layer and the convergence in the low layer enhanced the occurrence and development of MCS.In addition,the disturbance temperature field revealed the main source of energy which the occurrence and development of strong convective weather needed. 展开更多
关键词 meso-scale convective system Strong precipitation TBB Barnes band-pass wave filtering China
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Statistical characteristics of meso-scale vortex effects on the track of a tropical cyclone 被引量:2
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作者 罗哲贤 孙治安 平凡 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第4期581-585,共5页
This paper examines initial meso-scale vortex effects on the motion of a tropical cyclone (TC) in a system where coexisting two components of TC and meso-scale vortices with a barotropic vorticity equation model. Th... This paper examines initial meso-scale vortex effects on the motion of a tropical cyclone (TC) in a system where coexisting two components of TC and meso-scale vortices with a barotropic vorticity equation model. The initial mesoscale vortices are generated stochastically by employing Reinaud's method. The 62 simulations are performed and analysed in order to understand the statistical characteristics of the effects. Results show that the deflection of the TC track at t = 24 h induced by the initial meso-scale vortices ranges from 2 km to 37 km with the mean value of 13.4 km. A more significant deflection of the TC track can be reduced when several initial meso-scale vortices simultaneously appear in a smaller TC circulation area. It ranges from 22 km to 37 km with the mean value of 28 km, this fact implies that the initial meso-scale vortices-induced deflection may not be neglected sometimes. 展开更多
关键词 meso-scale vortex tropical cyclone statistical characteristics
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Case study on the three-dimensional structure of meso-scale eddy in the South China Sea based on a high-resolution model 被引量:3
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作者 XIA Changshui JUNG Kyung Tae +2 位作者 WANG Guansuo YIN Xunqiang GUO Jingsong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第2期29-38,共10页
Meso-scale eddies are important features in the South China Sea(SCS). The eddies with diameters of 50–200 km can greatly impact the transport of heat, momentum, and tracers. A high-resolution wave-tide-circulation ... Meso-scale eddies are important features in the South China Sea(SCS). The eddies with diameters of 50–200 km can greatly impact the transport of heat, momentum, and tracers. A high-resolution wave-tide-circulation coupled model was developed to simulate the meso-scale eddy in the SCS in this study. The aim of this study is to examine the model ability to simulate the meso-scale eddy in the SCS without data assimilations The simulated Sea Surface Height(SSH) anomalies agree with the observed the AVISO SSH anomalies well. The simulated subsurface temperature profiles agree with the CTD observation data from the ROSE(Responses of Marine Hazards to climate change in the Western Pacific) project. The simulated upper-ocean currents also agree with the main circulation based on observations. A warm eddy is identified in winter in the northern SCS. The position and domain of the simulated eddy are confirmed by the observed sea surface height data from the AVISO. The result shows that the model has the ability to simulate the meso-scale eddy in the SCS without data assimilation.The three-dimensional structure of the meso-scale eddy in the SCS is analyzed using the model result. It is found that the eddy center is tilted vertically, which agrees with the observation. It is also found that the velocity center of the eddy does not coincide with the temperature center of the eddy. The result shows that the model has the ability to simulate the meso-scale eddy in the SCS without data assimilations. Further study on the forming mechanism and the three-dimensional structure of the meso-scale eddies will be carried out using the model result and cruise observation data in the near future. 展开更多
关键词 meso-scale eddy South China Sea high-resolution wave-tide-circulation coupled model
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THE DYNAMICAL ANALYSIS OF THE STRUCTURE OF Β MESO-SCALE DOUBLE RAINBANDS IN MEIYU FRONT 被引量:1
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作者 王春明 王元 伍荣生 《Journal of Tropical Meteorology》 SCIE 2007年第2期120-131,共12页
In this paper, an idealized perturbation following the "surge-flow conceptual model" for typical Meiyu frontal structure is designed to explain the β meso-scale structure ofrainbands in the Meiyu front using a non-... In this paper, an idealized perturbation following the "surge-flow conceptual model" for typical Meiyu frontal structure is designed to explain the β meso-scale structure ofrainbands in the Meiyu front using a non-hydrostatic, full-compressible storm-scale model including multi-phase microphysical parameterization. In addition, sensitivity numerical experiment on the vertical distribution of the ambient meridional wind is conducted to investigate the generation mechanism of D meso-scale double rainbands. The results of numerical experiments show that the cool and dry downdraft invading strengthened by the environmental aloft northerly wind plays a very important role to the generation and maintenance of the β meso-scale double rainbands. Moreover, the intensity and scale of the dry and cool downdraft invading are related to the intensity of the second circumfluence induced by mass adjustment when the acceleration of the westerly jet aloft occurs. 展开更多
关键词 β meso-scale rainbands in Meiyu front dry and cool downdraft acceleration of westerly jet aloft
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Modeling development on the meso-scale reacting transport phenomena in proton exchange membrane fuel cells 被引量:1
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作者 Jianliang Yuan Yu Xiao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第3期370-378,共9页
The catalyst layer (CL) of proton exchange mem-brane fuel cell (PEMFC) involves various particles and pores in meso-scale, which has an important effect on the mass, charge (proton and electron) and heat transpo... The catalyst layer (CL) of proton exchange mem-brane fuel cell (PEMFC) involves various particles and pores in meso-scale, which has an important effect on the mass, charge (proton and electron) and heat transport coupled with the electrochemical reactions. The coarse-grained molecular dynamics (CG-MD) method is employed as a meso-scale structure reconstruction technique to mimic the self-organization phenomena in the fabrication steps of a CL. The meso-scale structure obtained at the equilibrium state is further analyzed by molecular dynamic (MD) software to provide the necessary microscopic parameters for understanding of multi-scale and-physics processes in CLs. The primary pore size distribution (PSD) and active platinum (Pt) surface areas are also calculated and then compared with the experiments. In addition, we also highlight the implementation method to combine microscopic elementary kinetic reaction schemes with the CG-MD approaches to provide insight into the reactions in CLs. The concepts from CG modeling with particle hydrodynamics (SPH) and the problems on coupling of SPH with finite element modeling (FEM) methods are further outlined and discussed to understand the effects of the meso-scale transport phenomena in fuel cells. 展开更多
关键词 CG-MD · meso-scale · Reaction · Catalyst layer · Fuel cell
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Propagation of shock waves in dry and wet sandstone:Experimental observations,theoretical analysis and meso-scale modeling
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作者 Chuang Liu Yang Wu +4 位作者 Xian-feng Zhang Jia-jie Deng Chen-yang Xu Wei Xiong Meng-ting Tan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2018年第5期513-521,共9页
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 paper.According to t... 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 paper.According 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. 展开更多
关键词 Dynamic impact Shock wave meso-scale simulation SANDSTONE
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On the Development of Meso-Scale Heavy Rain Parcels in China
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作者 章淹 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1995年第1期79-86,共8页
Heavy rains occur in China frequently, which often bring us floods and serious disasters in the summer half-year. The meso-scale heavy rain parcels (MHRP) in the mid-latitude are usually developed in following cases:I... Heavy rains occur in China frequently, which often bring us floods and serious disasters in the summer half-year. The meso-scale heavy rain parcels (MHRP) in the mid-latitude are usually developed in following cases:I.By the approaching, meeting and / or overlapping of different weather systems, when two or more different rainfall systems are getting to conjugate, some MHRPs could be developed, such as: 1) a new cold/warm front or squall line approaches an old front or squall, even when the old one is somewhat decrepit; 2) at the places where two or more synoptic systems with different characteristics are meeting together, such as the meeting of tropical cyclone with the cold airs coming from the mid- and / or high-latitudes, or the low latitude vortex meeting with the westerly trough; 3) at the intersections of some different weather systems, such as the intersection of drylines, squall lines or fronts moving from different directions; and 4) by the overlapping of rainfall parcels produced continuously from a meso-generation centre.II.Resonance Effect and Tibetan Plateau Influence are two reasons why high frequency of heavy and torrential rains arround the meiyu front is discussed also. 展开更多
关键词 meso-scale heavy rain parcels (MHRP) Forcing field Interactions of different weather systems Resonance effect Tibetan Plateau influence.
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Electrical Characteristics,Electrode Sheath and Contamination Layer Behavior of a Meso-Scale Premixed Methane-Air Flame Under AC/DC Electric Fields
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作者 陈琪 闫丽敏 +1 位作者 张浩 李国岫 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第5期569-576,共8页
Electrical characteristics of a nozzle-attached meso-scale premixed methane-air flame under low-frequency AC (0-4300 V, 0-500 Hz) and DC (0-3300 V) electric fields were studied. I-V curves were measured under diff... Electrical characteristics of a nozzle-attached meso-scale premixed methane-air flame under low-frequency AC (0-4300 V, 0-500 Hz) and DC (0-3300 V) electric fields were studied. I-V curves were measured under different experimental conditions to estimate the magnitude of the total current 10^0-10^2μA, the electron density 10^15-10^16 m^-3 and further the power dissipation 〈 0.7 W in the reaction zone. At the same time, the meso-scale premixed flame conductivity 10^-4-10^-3 Ω^-1. m^-1 as a function of voltage and frequency was experimentally obtained and was believed to represent a useful order-of magnitude estimate. Moreover, the influence of the collision sheath relating to Debye length (31-98 μm) and the contamination layer of an active electrode on measurements was discussed, based on the combination of simulation and theoretical analysis. As a result, the electrode sheath dimension was evaluated to less than 0.5 mm, which indicated a complex effect of the collision sheath on the current measurements. The surface contamination effect of an active electrode was further analyzed using the SEM imaging method, which showed elements immigration during the contamination layer formation process. 展开更多
关键词 meso-scale combustion low frequency AC electron-neutral collision collisionsheath contamination layer
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Analysis on the Meso-scale Characteristics of a Hail Process in Linyi Area
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作者 LIU Ying-jie CAO Xing-feng +2 位作者 ZHU Yi-qing WANG Qing-hua LI Bing-wen 《Meteorological and Environmental Research》 CAS 2011年第6期41-45,50,共6页
[Objective] The research aimed to study the meso-scale characteristics of a hail process in Linyi area. [Method] By comprehensively using MICAPS conventional observation data, automatic encryption ground station, MM5 ... [Objective] The research aimed to study the meso-scale characteristics of a hail process in Linyi area. [Method] By comprehensively using MICAPS conventional observation data, automatic encryption ground station, MM5 model product and Doppler weather radar data, a strong convective hail weather process which happened in Shandong Peninsula and southeast of Shandong on May 30, 2010 was analyzed. The circulation background and physical mechanism of strong convection weather occurrence, the features of meso- and micro-scale systems were discussed. Some occurrence and development rules of such weather were found. [Result] The strong convective weather was mainly affected by the cold vortex and translot. The high-altitude northwest airflow, low-level southwest airflow, dry and cold air at the high layer, warm and wet air at the low layer, forward-tilting trough caused the strong convective weather. The radar echo analysis showed that the radar echo in the process belonged to the typical multi-monomer windstorm echo, and the strong echo zone was in the forefront of echo. When the convection development was the strongest, the echo intensity reached 65 dBz, and the echo top height surpassed 11 km. As the development of windstorm monomer, the big-value zone of vertical liquid water content product had the jumping formation and disappearance. Moreover, there was obvious weak echo zone. The windstorm monomer moved to the southeast direction as the precipitation system. In the right front of monomer moving direction, there was hook echo feature. The evolution characteristics of radial speed field at the different elevation angles before and after the hail weather occurrence were analyzed. It was found that the radial speed field had some premonitory variations before the hail weather occurrence. Doppler radar product was used to improve the initial field of MM5 model, which could improve the forecast effect in the certain degree and the accuracy of short-time forecast and nowcasting. [Conclusion] The research accumulated the experience for the short-term forecast and nowcasting work of strong convective weather in future. 展开更多
关键词 HAIL Strong convective weather meso-scale characteristic Linyi area China
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Study on circulation and meso-scale eddies in the South China Sea in summer of 1998
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作者 许建平 薛惠洁 +1 位作者 侍茂崇 刘增宏 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2002年第4期469-481,共13页
By using wide scope ADCP data which were got during SCSMEX (South China Sea Monsoon Experiment) period in the summer of 1998, and comparing these data with numerical modelling result, the distribution and variation ch... By using wide scope ADCP data which were got during SCSMEX (South China Sea Monsoon Experiment) period in the summer of 1998, and comparing these data with numerical modelling result, the distribution and variation characteristics of the circulation and meso-scale eddies in the South China Sea (SCS) were studied. The results show that: (1) in the SCS, 18 different scale eddies or motion systems with characteristics similar to meso-scale eddy were found during the investigation; (2) a strong westward current was found in the south of the Taiwan Shoal; (3) the energy of those eddies west of 114°E was much stronger than that of the east;(4) and there exist many powerful meso-scale eddies in the Nansha region south of 12°N. The distributions of numerous eddies reflect the complexity of the circulation in the SCS. It seems that the formation of those eddies should be caused by joint work of wind, coast feature, bottom topography, water density, inertial force and continental shelf waves. 展开更多
关键词 Monsoon meso-scale eddy circulation the South China Sea
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Meso-scale circulation at the intermediate-depth east of Mindanao observed by Argo profiling floats 被引量:12
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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 《Science China Earth Sciences》 SCIE EI CAS 2010年第3期432-440,共9页
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-de... 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. 展开更多
关键词 Mindanao Current intermediate-depth CIRCULATION meso-scale eddy ARGO profiling FLOAT
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Meso-scale corrosion expansion cracking of ribbed reinforced concrete based on a 3D random aggregate model 被引量:3
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作者 Zhi-qiang ZHANG Yong-long LI +1 位作者 Xing-yu ZHU Xin-hua LIU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2021年第11期924-940,共17页
In reinforced concrete structures,corrosion of the rebar produces 2–6 times more corrosion product than the original material,creating pressure on the surrounding concrete,leading to cracking.The study of corrosion a... In reinforced concrete structures,corrosion of the rebar produces 2–6 times more corrosion product than the original material,creating pressure on the surrounding concrete,leading to cracking.The study of corrosion and cracking in reinforced concrete structures is therefore of great importance for enhancing the durability of concrete.Unlike many previous studies,we used ribbed rebar similar to that used commercially and considered the mechanical behavior of the interface transition zone(ITZ)between the aggregate and mortar to simulate the processes of corrosion and cracking of reinforced concrete structures.We explored the failure mode of the interface layer under uniform corrosion and the influence of different factors on the corrosion expansion cracking and the shedding mode of a concrete cover.This was achieved by establishing a three-phase meso-scale model of concrete based on secondary development of ABAQUS,simulating the mechanical behavior of the ITZ using a cohesive element,and establishing a rust expansion cracking model for single and multiple rebars.The results showed that:(1)Under uniform rust expansion,concrete cracks are distributed in a cross pattern with a slightly shorter lower limb.(2)When the corrosion rate is low,the ITZ is not damaged.With an increase in the corrosion rate,the proportion of elements with tensile damage in the ITZ first increases and then decreases.(3)In the case of a single rebar,the larger the cover thickness,the higher the corrosion rate corresponding to ITZ failure,and the arrangement of the rebar has little influence on the ITZ failure mode.(4)In the case of multiple rebars,the concrete cover cracks when the rebar spacing is small,and wedge-shaped spalling occurs when the spacing is large. 展开更多
关键词 Rebar corrosion 3D meso-scale model Cohesion model Interface transition zone Failure mode
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Focusing on the meso-scales of multi-scale phenomena-In search for a new paradigm in chemical engineering 被引量:16
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作者 Jinghai Li Wei Ge Wei Wang Ning Yang 《Particuology》 SCIE EI CAS CSCD 2010年第6期634-639,共6页
To celebrate the 90th birthday of Professor Mooson Kwauk, who supervised the multi-scale research at this Institute in the last three decades, we dedicate this paper outlining our thoughts on this subject accumulated ... To celebrate the 90th birthday of Professor Mooson Kwauk, who supervised the multi-scale research at this Institute in the last three decades, we dedicate this paper outlining our thoughts on this subject accumulated from our previous studies. In the process of developing, improving and extending the energy- minimization multi-scale (EMMS) method, we have gradually recognized that meso-scales are critical to the understanding of the different kinds of multi-scale structures and systems. It is a common challenge not only for chemical engineering but also for almost all disciplines of science and engineering, due to its importance in bridging micro- and macro-behaviors and in displaying complexity and diversity. It is believed that there may exist a common law behind meso-scales of different problems, possibly even in different fields. Therefore, a breakthrough in the understanding of meso-scales will help materialize a revolutionary progress, with respect to modeling, computation and application. 展开更多
关键词 meso-scale Multi-scale Complex system EMMS Multi-phase High performance computation
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Experimental study on the meso-scale milling of tungsten carbide WC-17.5Co with PCD end mills 被引量:2
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作者 Wei Zhao Asif Iqbal +2 位作者 Ding Fang Ning He Qi Yang 《Advances in Manufacturing》 SCIE CAS CSCD 2020年第2期230-241,共12页
Tungsten carbide is a material that is very difficult to cut,mainly owing to its extreme wear resistance.Its high value of yield strength,accompanied by extreme brittleness,renders its machinability extremely poor,wit... Tungsten carbide is a material that is very difficult to cut,mainly owing to its extreme wear resistance.Its high value of yield strength,accompanied by extreme brittleness,renders its machinability extremely poor,with most tools failing.Even when cutting with tool materials of the highest quality,its mode of cutting is mainly brittle and marred by material cracking.The ductile mode of cutting is possible only at micro leveIs of depth of cut and feed rate.This study aims to investigate the possibility of milling the carbide material at a meso-scale using polycrystaline diamond(PCD)end mills.A series of end milling experiments were performed to study the effects of cutting speed,feed per tooth,and axial depth of cut on performance measures such as cutting forces,surface roughness,and tool wear.To characterize the wear of PCD tools,a new approach to measuring the level of damage sustained by the faces of the cutter's teeth is presented.Analyses of the experimental data show that the effects of all the cutting parameters on the three performance measures are significant.The major damage mode of the PCD end mills is.found to be the intermittent micro-chipping.The progress of tool damage saw a long,stable,and steady period sandwiched between two short,abrupt,and intermittent periods.Cutting forces and surface roughness are found to rise with increments in the three cutting parameters,although the latter shows signs of reduction during the initial increase in cutting speed only.The results of this study find that an acceptable surface quality(average roughness Ra<0.2μm)and tool life(cutting length L>600mm)can be obtained under the conditions of the given cutting parameters.It indicates that milling with PCD tools at a meso-scale is a suitable machining method for tungsten carbides. 展开更多
关键词 Tungsten carbide meso-scale milling Polycrystalline diamond(PCD)end mill Cutting force Surface roughness Tool wear
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Important relationship between meso-scale structure and transfer coefficients in fluidized beds 被引量:6
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作者 Hongzhong Li 《Particuology》 SCIE EI CAS CSCD 2010年第6期631-633,共3页
Along with the fast development of computer technology and measurement techniques, fundamental research on fluidization is faced with both new challenges and opportunities. Among others, great attention should be focu... Along with the fast development of computer technology and measurement techniques, fundamental research on fluidization is faced with both new challenges and opportunities. Among others, great attention should be focused on the meso-scale structure of fluidized beds, to study the quantitative prediction theory and optimum control method for the meso-scale structure of fluidized beds, and to establish the modeling of the relationship between meso-scale structure and momentum transfer, heat transfer, mass transfer, and chemical reaction. These efforts, combined with advanced computer simulation, are expected to solve difficult problems in optimum control and scale-up of fluidized bed processes and equipment. 展开更多
关键词 meso-scale structureTransfer coefficientFluidized bedComputer simulation
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