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11.
针对D-InSAR地震形变监测中存在LOS(line of sight)视线向模糊的问题,该文构建了一种融合升降轨不同视线向干涉测量数据获取三维同震形变场的方法。以2017年九寨沟M_S7.0级地震为例,基于研究区的Sentine1_1A数据和SRTM(1″)DEM数据,采用二轨差分的D-InSAR技术,融合升降轨LOS向以及自定义视线向的干涉测量数据进行联合解算,获取了研究区三维同震形变场,解决了单一轨道雷达LOS提取结果不能准确反映地表三维形变场的问题。实验表明,此次地震造成了震中附近一定范围地表的沉降和东南向的滑移,并通过震区形变剖面图和形变等值线图,分析了形变场的空间分布以及此次地震所造成地表断裂的位置,认为此次地震与塔藏断裂、虎牙断裂存在关联性,其运动形式为主动盘逆冲的走滑型地震。 相似文献
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胶州湾三维变动边界的潮流数值模拟 总被引:35,自引:3,他引:35
基于Blumberg等(1986)的河口、陆架和海洋模式,引入变边界处理技术,建立了胶州湾三维变动边界的潮流模型,模型以σ-正交曲线坐标下三维非线性潮波方程为基本方程,引入2.5阶瑞封闭方程组,采用分裂算子法数值求解方程组,利用湍封闭方程求解垂直紊动粘滞系数,采用干湿网格方法模拟潮流漫滩过程,三维变动边界潮流模型计算结果与实测值吻合良好。 相似文献
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Three-dimensional numerical simulation of wind-induced barotropic circulation in the Gulf of Patras 总被引:1,自引:0,他引:1
Nikolaos Th. Fourniotis 《Ocean Engineering》2010,37(4):355-364
The barotropic, wind-induced circulation, which develops in the Gulf of Patras in Western Greece during the winter, is studied using three-dimensional numerical simulations. The simulations are performed using the numerical code MIKE 3 FM (HD). The Gulf's basin is bracketed between two sills, one on the west at the opening with the Ionian Sea and the other on the east at the Straits of Rio-Antirio at the opening with the Gulf of Corinth. The simulations show that the wind-induced flow creates strong currents near the coasts, which determine the sense of rotation of the gyres that develop in the Gulf. Strong currents are also created at the Rio-Antirio Straits. The wind-induced, barotropic currents do not seem to contribute to the direct replenishment of bottom waters, which recirculate between the two sills. Depending on the wind-speed forcing of the flow, the residence time of the waters in the Gulf of Patras is estimated to range from one week to one month. 相似文献
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Three-dimensional liquid sloshing in a tank with baffles 总被引:1,自引:0,他引:1
Dongming Liu 《Ocean Engineering》2009,36(2):202-52
A numerical model has been developed to study three-dimensional (3D) liquid sloshing in a tank with baffles. The numerical model solves the spatially averaged Navier-Stokes equations, which are constructed on a non-inertial reference frame having six degree-of-freedom (DOF) of motions. The large-eddy-simulation (LES) approach is employed to model turbulence by using the Smagorinsky sub-grid scale (SGS) closure model. The two-step projection method is employed in the numerical solutions, aided by the Bi-CGSTAB technique to solve the pressure Poisson equation for the filtered pressure field. The second-order accurate volume-of-fluid (VOF) method is used to track the distorted and broken free surface. The baffles in the tank are modeled by the concept of virtual boundary force (VBF) method. The numerical model is first validated against the available analytical solution and experimental data for two-dimensional (2D) liquid sloshing in a tank without baffles. The 2D liquid sloshing in tanks with baffles is then investigated. The numerical results are compared with other results from available literatures. Good agreement is obtained. Finally, the model is used to study 3D liquid sloshing in a tank with vertical baffles. The effect of the baffle is investigated and discussed. 相似文献
15.
In this paper we describe a 3D control-volume finite-element method to solve numerically the coupled partial differential equations (PDEs) governing geological processes involved in the evolution of sedimentary basins. These processes include sediment deposition and deformation, hydrocarbon generation, multiphase fluid flow, and heat transfer in deforming porous media. 相似文献
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Edgar Knobloch 《地球物理与天体物理流体动力学》2013,107(6):535-536
We present three-dimensional (3D) solutions of the magnetohydrostatic equations in the co-rotating frame of reference outside a magnetized rigidly rotating cylinder. We make no symmetry assumption for the magnetic field, but to be able to make analytical progress we neglect outflows and specify a particular form for the current density. The magnetohydrostatic equations can then be reduced to a single linear partial differential equation for a pseudo-potential U, from which the magnetic field can be calculated by differentiation. The equation for U can be solved by standard methods. The solutions can also be used to determine the plasma pressure, density and temperature as functions of all three spatial coordinates. Despite the obvious limitations of this approach, it can, for example, be used as a simple tool to create 3D models for the closed field line regions of rotating magnetospheres without rotational symmetry. 相似文献
18.
利用布设在唐山滦县震区30km×40km范围内的由88台数字和模拟地震仪组成的临时台阵,接收来自不同方向6个炮点激发产生的莫霍界面反射波走时,重建了台阵下1-9km深度的P,S波速度和Vp/Vs图像.结果表明。中、上地壳结构存在明显的横向不均匀性.北北东走向的滦县-卢龙断裂自地表向下至少延伸到8km深度处,并向北西方向倾斜.中、上地壳存在着近东西向的低速异常条带.这两组构造控制着该区的地震活动. 相似文献
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