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Numerical Investigation of Run-ups on Cylinder in steep Regular Wave

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China Ocean Engineering 2019年第5期33卷 601-607页

作者： FAN Xiang ZHANG Jing-xin LIU Hua Department of Engineering Mechanics MOE Key Laboratory of Hydrodynamics School of NAOCE Shanghai Jiao Tong University

The run-up on offshore structures induced by the steep regular wave is a highly nonlinear flow with a free surface. This article focuses on the investigation of the steep regular wave run-up on a single vertical cylinder by solving the Navier-Stokes equations. A numerical wave tank is established based on the open-source package to simulate the wave scattering induced by a vertical cylinder. The VOF method is applied to capture the large deformation and breaking of the free surface. The numerical model is validated by experimental results. The relative wave run-ups on the front face and the back face along the centerline of a cylinder are analyzed. The changes of the relative run-ups with the wave steepness, the relative diameter and the relative depth are studied. It is found that the relative run-ups on the front face and the back face of the cylinder depend mainly on the wave steepness and the relative diameter, while the dependence on the relative depth is weak. The empirical formulae are proposed to calculate the relative run-ups in terms of the wave steepness of incident regular waves and the relative diameter of a cylinder.

关键词： steep regular wave vertical cylinder run-up empirical formula numerical experiments

Low-temperature mineralization domain associated with the parallel positions between geochemical steep zones and geophysical gradient zones

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Chinese Science Bulletin 1999年第S2期44卷 166-168页

作者： ZHU Bingquan, DONG Yunpeng, CHANG Xiangyang and ZHANG Zhengwei Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

THE parallel strike of geochemical steep zones and geophysical gradient zones represent geochemicalboundaries with tectonic hiding and almost no magmatism, but there existed great variation of lithosphereor crustal thickness. Tectonically, these areas were located in the foreland basins of craton margin. Thesegeochemical boundaries were usually associated with the low-temperature mineralization and petroleumgeneration. The Nd, Sr and Pb isotopic evidence indicated that there still existed strong crustal-mantle interaction through fluid activation along deep-seated faults at the craton margin. Fig. 1 is the 207Pb/204 Pb-208Pb/204 Pb diagram, which shows the evident crust-mantle mixing for crude oil, chloroform bitumen-A,

关键词： low temperature mineralization domain geochemical steep zones geophysical gradient zones.

Tectonic implications of the isotopic geochemical steep zone in eastern Yunnan, China

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Chinese Science Bulletin 1999年第S2期44卷 195-196页

作者： DONG Yunpeng, ZHU Bingquan and CHANG Xiangyang Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

THE studies on geology, geochemistry and geophysics of mantle and crust show that there exist distinctvertical and lateral heterogenetics of the composition and structures of lithosphere. Especially, continentallithosphere possesses a complex rheological structure, which is one of the important factors controlling thedeformation and evolution of continent. Recently, the comprehensive studies in China and other countries suggest that the geochemical mapping and provincial division is a reliable method to reveal the heterogenetics, and Pb isotopic compositionhaving strong tectonic and regional characteristics. Therefore, Pb isotopic mapping is a key to revealingthe structure, formation and evolution of the lithosphere. Based on Pb isotopic mapping in South Chinacontinent, it has been revealed that there exists a Pb isotopic geochemical steep zone between Yangtzeblock and Cathaysia

关键词： tetonics isotopic steep zones Yunnan.

Characteristics of Proterozoic basements on the geochemical steep zones in the continent of China and their implications for setting of superlarge deposits

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Science China Earth Sciences 1998年第S1期41卷 54-64页

作者：朱炳泉常向阳邱华宁孙大中

Based on the Pb isotopic mapping of the continent of China and the geochemical data of Proterozoic basements, the steep zones of geochemical blocks of Cathaysia, Yangtze, North China, Central Mongolia, China\|Korea and Jiamusi are established. There are tight relationships between geochemical steep zones and setting of the superlarge deposits along with main mineralization zones. There are Proterozoic basements belonging to different blocks on both sides of geochemical steep zones in which volcanism and SEDEX were comprehensively developed and associated with reconstruction ore emplacement of dynamic metamorphism and magmatism from Jinning period to Mesozoic\|Cenozoic.

关键词： geochemical steep zone superlarge deposits Proterozoic.

Proterozoic copper metaliogenic framework and geochemistry steep zone in central Yunnan Province

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Chinese Science Bulletin 1999年第S2期44卷 163-164页

作者： CHANG Xiangyang, ZHU Bingquan and DONG Yunpeng Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China

THE wildly horizontal and vertical chemical heterogeneties, which result from the inchoate core-mantledifferentiation of the globe and the spatio-temporal difference of various regions in the globe, bring on themantle and crust from different landmass and oceans with markedly elemental and isotopic *** these signatures could be used to differentiate the attribute from various landmass or oceans andrecover the scent of kinematics and chemical geodynamics process. It is a quantificational method compared with the division by geotectonics facies and paleontologic fauna. Based on the geochemistry mapping of elements and multi-isotopic systematics of rocks derived frommantle and crust and combined with the studies on geophysical tomographic image, four type geochemicalprovinces can be distinguished. They are: (i) the Pacific (such as N-Pacific, N-Atlantic, the

关键词： Proterozoic copper metallogenesis geochemical steep zone Yunnan.

Comparative study of mining methods for reserves beneath end slope in flat surface mines with ultra-thick coal seams

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International Journal of Mining Science and Technology 2017年第6期27卷 1065-1071页

作者： Zha Zhengao Ma Li Li Kemin Ding Xiaohua Xiao Shuangshuang School of Mines China University of Mining and Technology Xuzhou 221116 China School of Energy Engineering Xi’an University of Science and Technology Xi’an 710054 China State Key Laboratory for Geomechanics & Deep Underground Engineering China University of Mining and Technology Xuzhou 221116 China

The paper aims to identify a reasonable method for mining ultra-thick coal seams in an end-slope in surface mine, With a case study of Heidaigou surface coal mine(HSCM), the paper conducted a comparative research on three mining methods, namely Underground Mining Method(UMM), Highwall Mining System(HMS) and Local steep Slope Mining Method(LSSMM). A model was firstly established to simulate the impact that UMM and HMS exert on monitoring points and surface deformation. The way that stripping and excavation amount varies with different slope angle, and the corresponding end slope stability were analyzed in the mode of LSSMM. Then a TOPSIS model was established by taking into account six indicators such as recovery ratio, technical complexity and adaptability, the impact on surface mining production, production safety and economic benefits. Finally, LSSMM was determined as the best mining method for mining ultra-thick coal seams in end slope in HSCM.

关键词： Ultra-thick coal seam End wall in surface mine Highwall Mining System Local steep slope Resource exploitation

Magnetoacoustic Waves in the Solar Stratified Atmosphere

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Chinese Physics Letters 2001年第12期18卷 1624-1627页

作者： ZHENG Hui-Nan WANG Shui S.T.Wu LI Bo Department of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026 Center for Space Plasma and Aeronomic Research and Department of Mechanical Engineering University of Alabama in HuntsvilleHuntsvilleAL 35899USA

The propagation of magnetoacoustic waves in the solar atmosphere consisting of the photosphere, chromosphere and corona has been studied numerically by time-dependent multi-dimensional magnetohydrodynamic (MHD) simulation. Pressure disturbances are introduced at the bottom of the chromosphere and at the bottom of the corona, respectively. The computational results show that incurred fast and slow MHD waves propagate away from the source of the disturbances. The fast MHD wave propagates as an expansive wave in the radial direction, while the slow one steepens and it may evolve into a slow shock. We suggest that the extreme ultraviolet imaging telescope wave observed by the SOHO and Moreton wave are a fast MHD wave propagating in the corona and in the chromosphere, respectively.

关键词： Solar Atmosphere steep

Differentiation of Continental Subduction Mode:Numerical Modeling

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Journal of Earth Science 2019年第4期30卷 809-822页

作者： Tuoxin Yang Pengpeng Huangfu Yan Zhang Guangdong Provincial Key Lab of Geodynamics and Geohazards School of Earth Sciences and EngineeringSun Yat-Sen UniversityGuangzhou 510275China Southern Laboratory of Ocean Science and Engineering Zhuhai 519082China Key Laboratory of Computational Geodynamics College of Earth SciencesUniversity of Chinese Academy of SciencesBeijing 100049China

The convergence of the multi-layered continental lithospheres with variable and complex thermal and rheological properties results in various modes of continental collision with distinct deformation behavior of the lithospheric mantle. Using high-resolution thermo-mechanical numerical models,we systematically investigated the effects of crustal rheological strength and the convergence rate on the continental subduction mode. The model results reveal three basic modes of continental subduction,including slab break-off,steep subduction and continental flat-slab subduction. Whether lithospheric mantle of the overriding plate retreats or not during convergence enables the division of the first two modes into two sub-types,which are dominated by the crustal rheological strength. The mode of slab break-off develops under the conditions of low/moderate rheological strength of the continental crust and low convergence rate. In contrast,continental flat-slab subduction favors the strong crust and the high convergence rate. Otherwise,continental steep subduction occurs. The numerical results provide further implications for Geodynamics conditions and physical processes of different modes of continental collision that occur in nature.

关键词： continental subduction slab break-off steep subduction continental flat-slab subduction numerical modeling

大型渠道陡坡薄壁混凝土衬砌施工技术研究与应用

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水力发电 2010年第12期36卷 45-47页

作者：和建生王良军葛洲坝集团第一工程有限公司湖北宜昌443002

南水北调中线干线京石段应急供水工程中4标及S34标石渠段衬砌属陡坡薄壁混凝土衬砌,采用常规方法衬砌存在弊端。经过不断比较和研究,最终创新出适合此类陡坡薄壁混凝土衬砌施工的自行滑模台车施工技术,将传统滑模与自行轨道台车相结合,... 详细信息

南水北调中线干线京石段应急供水工程中4标及S34标石渠段衬砌属陡坡薄壁混凝土衬砌,采用常规方法衬砌存在弊端。经过不断比较和研究,最终创新出适合此类陡坡薄壁混凝土衬砌施工的自行滑模台车施工技术,将传统滑模与自行轨道台车相结合,通过滑模技术解决陡坡混凝土成型难的问题,利用自行轨道台车解决施工效率低的问题。实践证明,其施工质量优良,满足设计要求,技术经济效果良好。该技术方案填补了我国大型渠道机械化衬砌技术的欠缺,在大型渠道陡坡薄壁混凝土衬砌施工中具有很好的推广价值和前景。

关键词：渠道陡坡壁混凝土衬砌施工技术研究与应用 steep Slope Thin Application 薄壁混凝土京石段应急供水工程衬砌施工台车南水北调中线技术经济效果滑模问题施工质量施工效率设计要求技术解决