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旋动式人工流产器旋流环的设计 被引量:4
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作者 程定超 孔令斌 +3 位作者 刘传永 张明 韩爱民 孙业 《医疗卫生装备》 CAS 2006年第2期81-82,共2页
简要介绍了旋动式人工流产器的工作原理、结构、组成,介绍了旋流环的结构、尺寸、材料及设计依据,同时简要介绍了旋动式人工流产器手术方法及其特点,提供了1种全新的人工流产手术方法和器械。
关键词 人工流产 旋动式人工流产器 旋流环
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旋动式人工流产器尼龙旋流环的研制 被引量:1
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作者 孔令斌 程定超 +3 位作者 刘传永 张明 韩爱民 孙业 《工程塑料应用》 CAS CSCD 北大核心 2003年第11期30-32,共3页
介绍旋动式人工流产器的工作原理、结构及组成,探讨旋流环的制备方法。通过对旋流环的模具设计、材料选择、工艺参数优化,研制出旋动式人工流产器尼龙旋流环。经检测,该旋流环的各项技术指标均达到设计要求,经临床初步试用证明,产品符... 介绍旋动式人工流产器的工作原理、结构及组成,探讨旋流环的制备方法。通过对旋流环的模具设计、材料选择、工艺参数优化,研制出旋动式人工流产器尼龙旋流环。经检测,该旋流环的各项技术指标均达到设计要求,经临床初步试用证明,产品符合临床要求。 展开更多
关键词 旋动式人工流产器 尼龙 旋流环 研制 材料选择 技术指标
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水平井环空旋流携砂流动规律实验研究 被引量:4
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作者 刘承婷 张维薇 +1 位作者 刘钢 闫作秀 《当代化工》 CAS 2017年第8期1585-1588,共4页
基于PIV测速技术对水平井环空管道内液固两相流动规律进行分析,研究不同环空流量、钻柱转速、流体粘度等相关因素。实验结果表明,随着环空流量、钻柱的转速和流体粘度的增加,岩屑床厚度降低,从而提高了岩屑的携带率。该实验研究成果可... 基于PIV测速技术对水平井环空管道内液固两相流动规律进行分析,研究不同环空流量、钻柱转速、流体粘度等相关因素。实验结果表明,随着环空流量、钻柱的转速和流体粘度的增加,岩屑床厚度降低,从而提高了岩屑的携带率。该实验研究成果可有效的为水平井的冲砂洗井工作提供理论依据。 展开更多
关键词 旋流 PIV测速技术 岩屑运移 轴向速度
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球形颗粒在幂律液体同心环空螺旋流场中的运移 被引量:2
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作者 张景富 陈家琅 《石油钻采工艺》 CAS CSCD 北大核心 1992年第6期1-9,33,共10页
在分析幂律液体同心环空螺旋流场特性的基础上,分析了球形岩屑颗粒在流场中的受力情况,给出了幂律液体层流螺旋流视牛顿粘度的计算公式,推导了不同绕流状态下颗粒沉降、上升速度公式,并给出了划分绕流状态新参数J的表达式及分区值。本... 在分析幂律液体同心环空螺旋流场特性的基础上,分析了球形岩屑颗粒在流场中的受力情况,给出了幂律液体层流螺旋流视牛顿粘度的计算公式,推导了不同绕流状态下颗粒沉降、上升速度公式,并给出了划分绕流状态新参数J的表达式及分区值。本文所得理论公式的数值模拟曲线与前人所得实验曲线在性状上得到了较好的吻合。 展开更多
关键词 旋转钻井 旋流 岩屑 钻井工艺 油田
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基于有限元的圆钢环缝旋流两段控冷过程温度场模拟 被引量:1
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作者 肖轶 《机械与电子》 2010年第8期9-13,共5页
借助ANSYS有限元分析软件,进行了温度场模拟,并建立了圆钢温度场预报模型.研究了圆钢环缝旋流控冷过程的热边界条件,分析了4种情况下圆钢温度场的分布及其变化规律.结果表明,相比常规控冷圆钢的晶粒度有明显细化,获得了圆钢在环缝旋流... 借助ANSYS有限元分析软件,进行了温度场模拟,并建立了圆钢温度场预报模型.研究了圆钢环缝旋流控冷过程的热边界条件,分析了4种情况下圆钢温度场的分布及其变化规律.结果表明,相比常规控冷圆钢的晶粒度有明显细化,获得了圆钢在环缝旋流两级控冷过程中的温度-时间历程曲线及其组织变化特点.模型的温度场数值模拟的结果与现场实验结果吻合良好.分析结果对于掌握圆钢的冷却规律、优化圆钢控冷工艺,以及开发新控制冷却技术具有实际指导意义. 展开更多
关键词 有限元 圆钢 旋流 控制冷却 温度场 数值模拟
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圆钢轧后环缝旋流冷却喷嘴的研制
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作者 肖轶 《机械工程与自动化》 2010年第6期76-78,共3页
设计了一种环缝旋流冷却喷嘴,并介绍了其在某钢厂圆钢控冷加工工艺中的应用情况,探讨了各工艺条件对圆钢最终组织、性能的影响。试验表明,该冷却喷嘴冷却能力约为常规直喷式冷却器的1.5倍,较常用湍流式冷却器冷却均匀,通过调节水流、水... 设计了一种环缝旋流冷却喷嘴,并介绍了其在某钢厂圆钢控冷加工工艺中的应用情况,探讨了各工艺条件对圆钢最终组织、性能的影响。试验表明,该冷却喷嘴冷却能力约为常规直喷式冷却器的1.5倍,较常用湍流式冷却器冷却均匀,通过调节水流、水压等参数控冷,可改善圆钢的性能。 展开更多
关键词 圆钢 旋流 冷却器 控制冷却
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电动旋转式人工流产器的研究 被引量:1
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作者 李震 刘传永 《中国医疗器械信息》 2007年第7期57-59,共3页
本文介绍了一种基于旋动的方式进行人工流产的新型医疗设备。该设备完全摒弃了负压吸引原理的束缚,通过软质旋流环的转动将妊娠物缠绕、牵脱、刮削并剥离出宫腔。从工作原理和系统设计方面对设备进行了具体分析。此种方法是一种全新的... 本文介绍了一种基于旋动的方式进行人工流产的新型医疗设备。该设备完全摒弃了负压吸引原理的束缚,通过软质旋流环的转动将妊娠物缠绕、牵脱、刮削并剥离出宫腔。从工作原理和系统设计方面对设备进行了具体分析。此种方法是一种全新的人工流产方式,具有较好的发展前景,并为人们对人工流产的方式提供了新的探索领域。 展开更多
关键词 人工流产 电动旋转 旋流环 单片机
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Formation Mechanism for the Anomalous Anticyclonic Circulation over Northeast Asia and the Japan Sea in Boreal Winter 1997/98 and the Spring of 1998 被引量:4
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作者 WANG Hai LIU Qinyu ZHENG Jian 《Journal of Ocean University of China》 SCIE CAS 2013年第2期312-317,共6页
A robust anomalous anticyclonic circulation (AAC) was observed over Northeast Asia and the Japan Sea in boreal win-ter 1997/98 and over the Japan Sea in spring 1998. The formation mechanism is investigated. On the bac... A robust anomalous anticyclonic circulation (AAC) was observed over Northeast Asia and the Japan Sea in boreal win-ter 1997/98 and over the Japan Sea in spring 1998. The formation mechanism is investigated. On the background of the vertically sheared winter monsoonal flow, anomalous rainfall in the tropical Indo-Western Pacific warm pool excited a wave train towards East Asia in the upper troposphere during boreal winter of 1997/98. The AAC over Northeast Asia and the Japan Sea is part of the wave train of equivalent barotropic structure. The AAC over the Japan Sea persisted from winter to spring and even intensified in spring 1998. The diagnostic calculations show that the vorticity and temperature fluxes by synoptic eddies are an important mechanism for the AAC over the Japan Sea in spring 1998. 展开更多
关键词 anomalous anticyclonic circulation Northeast Asia Japan Sea wave train synoptic eddy
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DIAGNOSIS OF WAVE ACTIVITY OVER RAINBAND OF LANDFALL TYPHOON 被引量:5
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作者 冉令坤 Abdul REHIM AL RAMANATHAN 《Journal of Tropical Meteorology》 SCIE 2009年第2期121-129,共9页
A generalized wave-activity density, which is defined as an absolute value of production of three-dimensional vorticity vector perturbation and gradient of general potential temperature perturbation, is introduced and... A generalized wave-activity density, which is defined as an absolute value of production of three-dimensional vorticity vector perturbation and gradient of general potential temperature perturbation, is introduced and its wave-activity law is derived in Cartesian coordinates. Constructed in an agoestrophic and nonhydrostatie dynamical framework, the generalized wave-activity law may be applicable to diagnose mesoscale weather systems leading to heavy rainfall. The generalized wave-activity density and wave-activity flux divergence were calculated with the objective analysis data to investigate the character of wave activity over heavy-rainfall regions. The primary dynamical processes responsible for disturbance associated with heavy rainfall were also analyzed. It was shown that the generalized wave-activity density was closely correlated to the observed 6-h accumulative rainfall. This indicated that the wave activity or disturbance was evident over the frontal and landfall-typhoon heavy-rainfall regions in middle and lower troposphere. For the landfall-typhoon rainband, the portion of generalized wave-activity flux divergence, denoting the interaction between the basic-state cyclonic circulation of landfall typhoon and mesoscale waves, was the primary dynamic process responsible for the evolution of generalized wave-activity density. 展开更多
关键词 dynamic meteorology wave-activity density wave-activity flux divergence landfall typhoon heavy-rainfall event
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Tropical Cyclone Tilts Under Vertically Varying Background Flows:Preliminary Results Based upon TCM4 Simulations 被引量:1
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作者 ZHENG Qikang LI Qingqing 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1066-1074,共9页
The characteristics of tropical cyclone(TC) tilts under vertically varying background flows were preliminarily examined in this study based on numerical simulations with the Tropical Cyclone Model version 4(TCM4).The ... The characteristics of tropical cyclone(TC) tilts under vertically varying background flows were preliminarily examined in this study based on numerical simulations with the Tropical Cyclone Model version 4(TCM4).The tilt magnitudes presented a linearly decreasing tendency in the simulation with the environmental wind speed vertically varying throughout the troposphere and in the simulation with the vertical wind shear concentrated in the lower troposphere,while the vortex tilt showed a linearly increasing tendency in magnitude in the simulation where the vertical shear was concentrated in the upper troposphere.The change in tilt magnitude was found to be related to the evolution of the penetration depth near the eyewall.When the shear was concentrated in the lower troposphere,the vortex tended to tilt downshear right during the early integration and underwent more precession processes.When the shear was concentrated in the upper troposphere,the vortex rapidly tilted downshear left during the early simulation and vortex precession was less frequently observed.The storms simulated in all experiments were finally in downshear-left tilt equilibrium. 展开更多
关键词 tropical cyclone TILT vertical wind shear penetration depth
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ASYMMETRIC RAINBAND BREAKING IN TYPHOON HAITANG(2005) BEFORE AND AFTER ITS LANDFALL 被引量:2
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作者 丁治英 王勇 +1 位作者 沈新勇 徐海明 《Journal of Tropical Meteorology》 SCIE 2011年第3期276-284,共9页
Using the WRF(Weather Research Forecast)model,this work performed analysis and simulation on the rainband change during the landfall of Typhoon Haitang(2005)and found that breaking may occur over land and oceans leads... Using the WRF(Weather Research Forecast)model,this work performed analysis and simulation on the rainband change during the landfall of Typhoon Haitang(2005)and found that breaking may occur over land and oceans leads to distinct asymmetric precipitation.The breaking is related to the topographic effect as well as interactions between the typhoon and midlatitude systems at upper levels.During the landfall,divergent flows at the 200-hPa level of the South-Asian high combined with divergent flows at the periphery of the typhoon to form a weak,inverted trough in the northwest part of the storm,with the mid- and low-level divergence fields on the west and northwest side of the typhoon center maintaining steadily.It intensifies the upper-level cyclonic flows,in association with positive vorticity rotating counterclockwise together with air currents that travel stepwise into a vorticity zone in the vicinity of the typhoon core, thereby forming a vorticity transfer belt in 22–25°N that extends to the eastern part of the storm.It is right here that the high-level vorticity band is subsiding so that rainfall is prevented from developing,resulting in the rainbelt breaking,which is the principal cause of asymmetric precipitation occurrence.Migrating into its outer region,the banded vorticity of Haitang at high levels causes further amplification of the cyclonic circulation in the western part and transfer of positive vorticity into the typhoon such that the rainband breaking is more distinct. 展开更多
关键词 TYPHOON rainband asymmetric precipitation WRF interactions
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Effect of a cyclonic flotation column on the separation of magnesium from phosphate ore 被引量:8
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作者 Li Guosheng Liu Jiongtian Cao Yijun Wang Dapeng 《Mining Science and Technology》 EI CAS 2011年第5期647-650,共4页
This study was performed to investigate the effects of the cyclonic separation mechanism on the removal of magnesium from phosphate ore. An analysis of the particle-bubble collision mechanism in a cyclonic force field... This study was performed to investigate the effects of the cyclonic separation mechanism on the removal of magnesium from phosphate ore. An analysis of the particle-bubble collision mechanism in a cyclonic force field was used to design two different pulp circulation systems for a cyclonic-static micro-bubble flotation column (FCSMC). Experiments comparing the two conditions were then conducted. Size analysis of the feed and separated products was conducted with a BXF cyclone size analyzer. The results show that about 34.60% of the total MgO content in the feed exists in the -10 μm fraction. This demonstrates that magnesium removal from phosphate ore has the characteristics of a micro-fine particle flotation problem. Under conditions of cyclonic circulation the MgO level of the concentrate is 1.74g, which is lower than that obtained from the column operated in direct-flow circulation by 0.34%, These results indicate that the cyclonic circulation mechanism of the FCSMC can promote removal of micro-fine particles containing magnesium. This is attributed to the function of surface flotation and to the reduction of the lower separation limit under conditions of cyclonic circulation. 展开更多
关键词 Flotation columnCyclonic separationPhosphate oreRemoval of magnesium
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Vorticity Budget Study on the Seasonal Upper Circulation in the Northern South China Sea from Altimetry Data and a Numerical Model 被引量:1
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作者 CAI Shuqun ZHENG Shu HE Yinghui 《Journal of Ocean University of China》 SCIE CAS 2012年第4期455-464,共10页
Based on the EOF analyses of Absolute Dynamic Topography satellite data, it is found that, in summer, the northern South China Sea (SCS) is dominated by an anticyclonic gyre whilst by a cyclonic one in winter. A con... Based on the EOF analyses of Absolute Dynamic Topography satellite data, it is found that, in summer, the northern South China Sea (SCS) is dominated by an anticyclonic gyre whilst by a cyclonic one in winter. A connected single-layer and two-layer model is employed here to investigate the dynamic mechanism of the circulation in the northern SCS. Numerical experi- ments show that the nonlinear term, the pressure torque and the planetary vorticity adveetion play important roles in the circulation of the northern SCS, whilst the contribution by seasonal wind stress curl is local and limited. Only a small part of the Kuroshio water intrudes into the SCS, it then induces a positive vorticity band extending southwestward from the west of the Luzon Strait (LS) and a negative vorticity band along the 200 m isobath of the northern basin. The positive vorticity field induced by the local summer wind stress curl is weaker than that induced in winter in the northern SCS. Besides the Kuroshio intrusion and monsoon, the water trans- ports via the Sunda Shelf and the Sibutu Passage are also important to the circulation in the northern SCS, and the induced vorticity field in summer is almost contrary to that in winter. The strength variations of these three key factors (Kuroshio, monsoon and the water transports via the Sunda Shelf and the Sibutu Passage) determine the seasonal variations of the vorticity and eddy fields in the northern SCS. As for the water exchange via the LS, the Kuroshio intrusion brings about a net inflow into the SCS, and the monsoon has a less effect, whilst the water transports via the Sunda Shelf and the Sibutu Passage are the most important influencing factors, thus, the water exchange of the SCS with the Pacific via the LS changes dramatically from an outflow of the SCS in summer to an inflow into the SCS in winter. 展开更多
关键词 KUROSHIO South China Sea circulation mosoon VORTICITY bifurcation of North Equatorial Current
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Experimental study on the spatial distribution of particle rotation in the upper dilute zone of a cold CFB riser 被引量:1
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作者 Xue-cheng WU Qin-hui WANG +3 位作者 Chen TIAN Zhong-yang LUO Meng-xiang FANG Ke-fa CEN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第7期922-931,共10页
Particle rotation plays an important role in gas-solid flows. This paper presents an experimental investigation on the spatial distribution of average rotation speed for glass beads in the upper dilute zone of a cold ... Particle rotation plays an important role in gas-solid flows. This paper presents an experimental investigation on the spatial distribution of average rotation speed for glass beads in the upper dilute zone of a cold circulating fluidized bed(CFB) riser. It is shown that in the horizontal direction,the average rotation speed in the near-wall area is larger than that in the center area,while in the vertical direction,it decreases as the height increases. The reason resulting in this distribution is analyzed by considering several factors including particle size,particle shape,particle number density,particle collision behavior,and the surrounding flow field,etc. The effects of CFB operation conditions on the spatial distribution of average rotation speed are also studied. The results show that the increasing superficial gas velocity increases the average rotation speed of particles in the near wall area but takes nearly no effect on that in the center area. The external solids mass flux,however,takes the opposite effect. It is found that the average rotation speeds of particles in both areas are increased as the total amount of bed material increases. 展开更多
关键词 Particle rotation Gas-solid two-phase flow Circulating fluidized bed (CFB)
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The Relationship between Precipitation and Airflow over the Tibetan Plateau in Boreal Summer
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作者 LI Fei FENG Juan 《Atmospheric and Oceanic Science Letters》 2012年第3期176-182,共7页
Based on the observation data and the reanalysis datasets, the variability and the circulation features influencing precipitation in the Tibetan Plateau (TP) are investigated. Taking into account the effects of topogr... Based on the observation data and the reanalysis datasets, the variability and the circulation features influencing precipitation in the Tibetan Plateau (TP) are investigated. Taking into account the effects of topography, surface winds are deconstructed into flow-around and flow-over components relative to the TP. Climatologically, the flow-around component mainly represents cyclonic circulation in the TP during the summer. The transition zone of total precipitation in the summer parallels the convergence belt between the southerlies and the northerlies of the flow-over component. The leading mode of rainfall anomalies in the TP has a meridional dipole structure, and the first principal component (PC1) mainly depicts the variation of rainfall in the southern TP. The wet southern TP experiences strengthened flow-over, which in turn mechanistically favors intensified ascent forced by the flow-over component. In addition, variations in the Indian summer monsoon (ISM) have an important role in influencing the flow over the southern TP, and the ISM ultimately impacts the precipitation over southern TP. 展开更多
关键词 flow around flow over the Tibetan Plateau Indian summer monsoon index
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THREE-DIMENSIONAL BAROCLINIC NUMERICAL SIMULATION OF THE SOUTH CHINA SEA CIRCULATION'S SEASONAL CHARACTERISTICS II. MIDDLE AND DEEP CIRCULATION 被引量:1
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作者 蔡树群 甘子钧 +1 位作者 苏纪兰 刘秦玉 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第1期9-15,共7页
A three-dimensional baroclinic shelf sea model’s numerical simulation of the South China Sea (SCS) middle and deep layer circulation structure showed that: 1. In the SCS middle and deep layer, a southward boundary cu... A three-dimensional baroclinic shelf sea model’s numerical simulation of the South China Sea (SCS) middle and deep layer circulation structure showed that: 1. In the SCS middle and deep layer, a southward boundary current exists along the east shore of the Indo-China Peninsula all year long. A cyclonic eddy (gyre) is formed by the current in the above sea areas except in the middle layer in spring, when an anticyclonic eddy exists on the eastern side of the current. In the deep layer, a large-scale anticyclonic eddy often exists in the sea areas between the Zhongsha Islands and west shore of southern Luzon Island. 2. In the middle layer in summer and autumn, and in the deep layer in autumn and winter, there is an anticyclonic eddy (gyre) in the northeastern SCS, while in the middle layer in winter and spring, and in the deep layer in spring and summer, there is a cyclonic one. 3. In the middle layer, there is a weak northeastward current in the Nansha Trough in spring and summer, while in autumn and winter it evolves into an anticyclonic eddy (gyre), which then spreads westward to the whole western Nansha Islands sea areas. 展开更多
关键词 numerical simulation model South China Sea CIRCULATION EDDY MONSOON
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Subthermocline anticyclonic gyre east of Mindanao and its relationship with the Mindanao Undercurrent
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作者 宋丽娜 李元龙 +1 位作者 刘传玉 王凡 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第6期1303-1318,共16页
The quasi-permanent anticyclonic gyre (ACG) east of Mindanao is a dominant feature of the subthermocline circulation in the southem Philippine Sea, and it is believed closely associated with the continuous northward... The quasi-permanent anticyclonic gyre (ACG) east of Mindanao is a dominant feature of the subthermocline circulation in the southem Philippine Sea, and it is believed closely associated with the continuous northward alongshore flow of the Mindanao Undercurrent (MUC). In this study, the structure and variability of this ACG were investigated using the 1950-2012 output of the Oceanic General Circulation Model for the Earth Simulator (OFES), which can reproduce well the structure of the climatological intermediate-layer circulation and satellite-observed sea level variations in the southern Philippine Sea. Between 26.8-27.3 ao, the ACG covers a large area from the Mindanao coast to 131 ~E and from 3~N to 10~N. Its anticyclonic flow structure is unrelated to the surface Halmahera Eddy. The eddy-resolving simulation of the OFES revealed that the ACG consists of two components. The southern ACG (SACG) is centered at -6~N, while the northern ACG (NACG) is centered at -10~N. Seasonal and interannual variations of the ACG are linked to the variations of the northward MUC transport along the Mindanao coast, and the role of the SACG is more important than the NACG. Stronger (weaker) ACGs lead to greater (smaller) MUC transport. On the interannual timescale, the SACG shows a spectrum peak at 4-8 years, while the NACG has enhanced power within the 3-5-year band. A lead-lag correlation analysis indicates that interannual variations of the ACGs and the MUC transport are partly associated with the E1 Nifio-Southern Oscillation. Possible causes for the ACG variability are discussed. 展开更多
关键词 subthermocline circulation anticyclonic gyre Mindanao Undercurrent seasonal and interannual variability Halmahera Eddy
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Sediment Movement in Periodic Alternating Current 被引量:11
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作者 CAOZude KONGLingshuang LIUDefu 《Journal of Ocean University of Qingdao》 2002年第2期201-205,共5页
The present paper summarizes the results of previous studies, including the structure and principle of the rotary ring flume for researching the fine sediment movement, the mechanism of the flume, method of eliminatin... The present paper summarizes the results of previous studies, including the structure and principle of the rotary ring flume for researching the fine sediment movement, the mechanism of the flume, method of eliminating the influence of the centrifugal force and sediment movement experiments with periodic alternating current. Also included are the experiment-based relationship among sediment concentration, bed shear stress and silt carrying capacity, a proposed erosion-deposition function and bed erosion-deposition calculation together with the results of verification. 展开更多
关键词 rotary ring flume periodic alternating current hydraulic characteristics of sediment erosion-deposition function
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The Seasonal Variations of the Climatic Circulation of the Black Sea along the Axis of Divergence Zone
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作者 Olga Andrianova Radomir Belevich 《Journal of Earth Science and Engineering》 2013年第7期506-514,共9页
The spatial position, seasonal variability and intensity of the main flow and the cyclonic circulation of the Black Sea waters along the axis of the divergence were identified. Corresponding calculations were done wit... The spatial position, seasonal variability and intensity of the main flow and the cyclonic circulation of the Black Sea waters along the axis of the divergence were identified. Corresponding calculations were done with using of the dynamic method and based on the climate data set of temperature and salinity for the surface and intermediate layers of the Black Sea. The important role of spring floods on the rivers of the northern-western Black Sea in the development of the water circulation features was shown because this river's water and main Black Sea current interact with the periphery of the western and eastern cyclonic circulation. This process is dominated at the western part sea surface cyclone: in spring and at eastern, in summer and autumn. The flow rate and nature of seasonal migration cyclonic centers were estimated. The results of research are based on a relatively large scale (40' latitude and 60' longitude) averaging and we have identified the main area of water divergence. Small, localized areas of convergence and divergence of flow that are presented in the Black Sea were not included into the scope of our research. 展开更多
关键词 Black Sea divergence zone seasonal variations temperature SALINITY river's water main flow gyres.
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Model Evaluation and Projection on the Linkage between Hadley Circulation and Atmospheric Background Related to the Tropical Cyclone Frequency over the Western North Pacific
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作者 ZHOU Bo-Tao 《Atmospheric and Oceanic Science Letters》 2012年第6期473-477,共5页
The performance of climate models in simulating the linkage of the spring Hadley circulation (HC) to the vertical zonal wind shear and atmospheric divergence in the lower and upper troposphere, which are related to th... The performance of climate models in simulating the linkage of the spring Hadley circulation (HC) to the vertical zonal wind shear and atmospheric divergence in the lower and upper troposphere, which are related to the tropical cyclone frequency over the western North Pacific (WNPTCF) during June-September (JJAS), is evaluated on the basis of the 20th century climate simulations (20C3M). It is found that four models can simulta-neously reproduce the pattern revealed in the observation, with the spring HC in the Northern Hemisphere being positively correlated to the vertical zonal wind shear in the major tropical cyclone (TC) genesis region and negatively (positively) correlated to the atmospheric diver- gence in the upper (lower) troposphere over the western North Pacific (WNP) in the following JJAS. These four models are further used to project their relationship in the late 21st century under the A1B scenario. The results show that the association of spring HC with the vertical zonal wind shear and the upper-and lower-tropospheric divergence over the WNP will weaken in the late 21st century, thereby resulting in a weak relationship between the spring HC and the JJAS WNPTCF. 展开更多
关键词 Hadley circulation atmospheric circulation tropical cyclone assessment PROJECTION
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