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21.
A fully nonlinear numerical model based on a time-domain higher-order boundary element method (HOBEM) is founded to simulate the kinematics of extreme waves. In the model, the fully nonlinear free surface boundary conditions are satisfied and a semi-mixed Euler-Lagrange method is used to track free surface; a fourth-order Runga-Kutta technique is adopted to refresh the wave elevation and velocity potential on the free surface at each time step; an image Green function is used in the numerical wave tank so that the integrations on the lateral surfaces and bottom are excluded. The extreme waves are generated by the method of wave focusing. The physical experiments are carried out in a wave flume. On the horizontal velocity of the measured point, numerical solutions agree well with experimental results. The characteristics of the nonlinear extreme-wave kinematics and the velocity distribution are studied here.  相似文献   
22.
介绍了针对某批大型油罐的沉降监测数据处理软件制作过程,采用了Excel电子表格软件在VBA可视化编程环境下完成,实现了工程测量数据的及时处理分析。  相似文献   
23.
作为地球物理场的一个分支,地温场在理论和应用研究方面与其它地球物理场一样,也主要是依靠数学方法和物理模型实验的方法来进行的。本文讨论了地热异常水槽模型实验的理论原理;介绍了实验方法技术、实验结果和实际应用效果。  相似文献   
24.
谭鸿赞 《铀矿地质》1990,6(3):145-151
本文通过热力学的计算方法,确定了测老庙盆地水中铀的存在形式,分析了铀在水中的迁移规律和沉淀条件。并应用饱和指数的找矿机理,对测老庙盆地的找矿前景提出了水文地球化学依据。  相似文献   
25.
程先云  刘洪禄  郑凡东 《水文》2007,27(6):42-45
引入水箱模型进行城市地下排水设施降雨一侵入水的模拟,探讨了初期蓄流值对模拟结果的影响并提出了相应的解决办法;由于模型参数多、非线性,参数的率定采用通用优化分析计算平台PowerFit,并获得了满意的结果,表明:①水箱模型适用于地下排水设施雨洪模拟和预测,可为市政规划设计和城市灾害预报提供可靠依据;②PowerFit全局优化能力强、简单易用,可广泛应用于水利水电等工程领域中的优化计算。  相似文献   
26.
本文采用液压阻尼系统(HDS)控制立式圆柱钢制储罐的地震反应,建立了安装HDS储罐的力学分析模型,并进行了数值计算,从频域对安装HDS后储罐的地震响应进行了分析,研究了HDS的减震效果和HDS和HDS参数对储罐地震反应的影响。  相似文献   
27.
某油罐因地基发生不均匀沉降而倾斜,本文通过对油罐发生均匀沉降的原因分析,提出了倾斜油罐纠偏设计及地基处理方案,叙述了地基处理及纠偏施工方法,施工处理后经过半年的使用观察,效果良好。  相似文献   
28.
The Conrad Blucher Institute for Surveying and Science (Texas A&M University––Corpus Christi) has conducted numerous petroleum experiments at the Shoreline Environmental Research Facility (Corpus Christi, Texas, USA). The meso-scale facility has multiple wave tanks, permitting some control in experimental design of the investigations, but allowing for real-world conditions. This paper outlines the evolution of a materials balance approach in conducting petroleum experiments at the facility. The first attempt at a materials balance was during a 1998 study on the fate/effects of dispersant use on crude oil. Both water column and beach sediment samples were collected. For the materials balance, the defined environmental compartments for oil accumulation were sediments, water column, and the water surface, while the discharge from the tanks was presumed to be the primary sink. The “lessons learned” included a need to quantify oil adhesion to the tank surfaces. This was resolved by adhering strips of the polymer tank lining to the tank sides that could be later removed and extracted for oil. Also, a protocol was needed to quantify any floating oil on the water surface. A water surface (oil slick) quantification protocol was developed, involving the use of solid-phase extraction disks. This protocol was first tested during a shoreline cleaner experiment, and later refined in subsequent dispersant effectiveness studies. The effectiveness tests were designed to simulate shallow embayments which created the need for additional adjustments in the tanks. Since dispersant efficacy is largely affected by hydrodynamics, it was necessary to scale the hydrodynamic conditions of the tanks to those expected in our prototype system (Corpus Christi Bay, Texas). The use of a scaled model permits the experiment to be reproduced and/or evaluated under different conditions. To minimize wave reflection in the tank, a parabolic wave dissipater was built. In terms of materials balance, this design reduced available surface area as a sink for oil adsorption.  相似文献   
29.
The objectives of this study are (1) to understand the subsurface hydrology in the Aurku area, Chiayi County, southern Taiwan, and (2) to determine the interaction between the manmade lake and groundwater level through the recharge produced by infiltration by on‐site investigation and laboratory sand tank simulation. The manmade lake was selected as the field site for groundwater recharge effect so as to assess the role of infiltration from the aquaculture ponds in this area. These results can be used as reference for future application of constructing a series of manmade lakes. The field experiment was performed to measure the infiltration rate of the manmade lake by using the water balance method and double‐ring infiltration test. The results demonstrated that the manmade lake had helped the recharge of the groundwater. Raising or maintaining a higher water level of the manmade lake can promote higher infiltration. When the groundwater level is equal to or higher than the bottom of the manmade lake, infiltration will slow or cease. The field experiment and laboratory sand tank simulation demonstrated that the infiltration rate increased with the higher storage depth of the manmade lake. The laboratory simulation also indicated that while the groundwater level was lower than the bottom of manmade lake (i.e. the reference level) and the initial water depth (3 cm) was equal to or greater than 50% of the full water storage depth, the infiltration depth increased with time. However, the infiltration depth would be very small or nearly zero when the groundwater level was higher than the bottom of the manmade lake. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
30.
高桩挡板透空式防波堤消浪性能数值研究   总被引:1,自引:1,他引:0  
以RANS方程为控制方程,基于有限体积法,在动量方程中添加源项,建立了具有造波‐消波功能的数值波浪水槽。利用建立的源项造波数值波浪水槽,模拟了高桩挡板透空式防波堤在规则波作用下的消浪效果,完整地再现了堤前堤后的流态,分析了挡板相对入水深度对透浪系数的影响。在与试验值及拉帕公式对比后发现,数模计算结果与试验值较接近,拉帕公式偏大。研究了堤顶相对宽度、相对水深、相对波高对透浪系数的影响并提出修正公式,修正公式与计算值和试验值吻合较好。  相似文献   
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