Corrosion of rebar in concrete and its prevention          下载免费PDF全文

LIU Xue-qing  CHEN Lie  HOU Bao-rong 《海洋科学》2008,32(10)

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A second-order particle tracking method     

Seok Lee  Heung-Jae Lie  Kyu-Min Song  Chong-Jeanne Lim 《Ocean Science Journal》2005,40(4):201-208

An accurate particle tracking method for a finite difference method model is developed using a constant acceleration method. Being assumed constant temporal and spatial gradients, the new method permits temporal-spatial variability of particle velocity. Test results in a solid rotating flow show that the new method has second-order accuracy. The performance of the new method is compared with that of other methods; the first-order Euler forward method, and the second-order Euler predictorcorrector method. The new method is the most efficient method among the three. It is more accurate and efficient than the other two.  相似文献   

准噶尔盆地北三台凸起新近系含铀砂层分布预测     

蔡义峰  薛冽  彭文利  黄新华  马效杰 《新疆地质》2021,(1):118-123

通过对准噶尔盆地北三台凸起油气钻井的录、测井等资料分析发现,在新近系沙湾组底部发育一套异常高自然伽马砂砾岩,其中B311井GR值最高达1732.58 API,预示该区具有良好铀资源勘探前景。为准确预测该区含铀砂岩分布,通过精细的合成记录标定,对该含铀砂层提取地震属性。通过多属性融合与分析,预测含铀砂层平面分布,进而利用地震波形指示反演技术预测含铀砂层的垂向和平面展布特征,进一步提高预测精度,指出了铀矿勘探的有利区域。  相似文献   

Crack propagation analysis with Galerkin boundary element method     

K. Xu  S. T. Lie  Z. Cen 《国际地质力学数值与分析法杂志》2004,28(5):421-435

This paper describes the application of symmetric Galerkin boundary element methods (SGBEM) for the analysis of a 2D crack propagation problem. The sub-domain SGBEM for crack problem is derived. The coefficient matrix is completely symmetric. Cohesive crack model is used to simulate crack propagation. The increment control method for crack propagation and the method for unknown crack propagation path have been derived for high-order element. Two-stage interpolation method called the ‘quasi-higher order element method’ (QHOEM) is then proposed to solve the double integrals. In the initial stage, it uses higher order elements to interpolate the field variables, and for the numerical integration involved, it further uses interpolation functions to decompose the higher order elements into lower order elements so that the existing analytical integration can be applied. A finite rectangular plate containing a centre crack growth and four-points bending beam problem have been analysed to check the accuracy of the proposed method. For actual application, a dam buttress with an edge crack has been analysed and the results are found to be in agreement with the other numerical and experimental results. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

Fully-implicit simulation of vertical-equilibrium models with hysteresis and capillary fringe     

Halvor Møll Nilsen  Knut-Andreas Lie  Odd Andersen 《Computational Geosciences》2016,20(1):49-67

Geological carbon storage represents a new and substantial challenge for the subsurface geosciences. To increase understanding and make good engineering decisions, containment processes and large-scale storage operations must be simulated in a thousand year perspective. A hierarchy of models of increasing computational complexity for analysis and simulation of large-scale CO₂ storage has been implemented as a separate module of the open-source Matlab Reservoir Simulation Toolbox (MRST). This paper describes a general family of two-scale models available in this module. The models consist of two-dimensional flow equations formulated in terms of effective quantities obtained from hydrostatic reconstructions of vertical pressure and saturation distributions. The corresponding formulation is fully implicit and is the first to give a mass-conservative treatment and include general (non-linearized) CO₂ properties. In particular, the models account for compressibility, dissolution, and hysteresis effects in the fine-scale capillary and relative permeability functions and can be used to accurately and efficiently study the combined large-scale and long-term effects of structural, residual, and solubility trapping.  相似文献   

川西坳陷天然气运聚模拟研究   总被引：5，自引：0，他引：5  

曹烈  周兴毅  邓永富  安凤山 《矿物岩石》2000,20(3):75-80

四川盆地川西坳陷蕴藏有丰富的天然气资源,通过多年勘探、发现其成藏聚集规律复杂,利用天然气运移模拟研究能有效地降低钻井风险。通过适合川西坳陷地质特征的二维沉积史、地热史、生烃史的模拟,证实了川西坳陷存在两个烃高峰期（三叠纪末和侏罗纪末－白垩纪）,模拟出相应于两个生烃高峰值时的古构造,明确了砂岩的致密化进程,采用动态运移模型使得天然气运移模拟更加精确,并提出几个有处勘探区。  相似文献   

A fast marching method for reservoir simulation   总被引：1，自引：0，他引：1  

K. Hvistendahl Karlsen  K.-A. Lie  N.H. Risebro 《Computational Geosciences》2000,4(2):185-206

We present a fast marching level set method for reservoir simulation based on a fractional flow formulation of two-phase, incompressible, immiscible flow in two or three space dimensions. The method uses a fast marching approach and is therefore considerably faster than conventional finite difference methods. The fast marching approach compares favorably with a front tracking method as regards both efficiency and accuracy. In addition, it maintains the advantage of being able to handle changing topologies of the front structure. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

有机烃新方法在金矿床快速定位预测中的应用:以陕西八卦庙特大型金矿床为例   总被引：4，自引：0，他引：4  

吴烈善  韦龙明 《地球化学》2001,30(6):579-584

有机质对金属元素的迁移、沉积和富集成矿有重要的作用，有机烃是有机质最终的裂解产物，具有很强的挥发性和穿透性。研究发现，八卦庙金矿床有机烃与金矿体品位呈密切相关关系，矿床的矿化富集中心也是有机烃的浓集中心。利用有机烃的这一特点可以进行隐伏金矿床的定位预测研究。  相似文献   

江西省区域岩矿石物性数据统计特征     

言会  李磊  张立为  郭友钊 《物探与化探》2004,28(1):19-22,31

介绍以江西省全境和两个地层区为空间范围内的53741个岩矿石密度数据、12677个磁化率数据、12424个剩磁强度数据的岩石物性统计特征,供在江西省境内进行矿区物探工作时参考。  相似文献   

大城市边缘区人居环境系统特征研究   总被引：4，自引：0，他引：4  

祁新华  程煜  陈烈 《亚热带资源与环境学报》2007,2(3):63-68

大城市边缘区人居环境系统是一个开放的复杂巨系统,具备动态性、整体性、开放性、层次性、可控性等基本特征.中国在长期执行城乡"二元"体制下,大城市边缘区明显的边缘效应叠加上人居环境发展进程的"二元化",形成中国大城市边缘区人居环境突出的"二元"性特征.从地理位置、人口结构、土地利用方式、地域景观、基础设施建设、社区形态、管理方式等方面均表现出与城市核心区及乡村人居环境不同的特点.  相似文献