珠江口磨刀门整治前后水动力数值模拟   总被引：2，自引：0，他引：2  

吕海滨  吴超羽  刘斌 《海洋科学》2006,30(11):58-63

磨刀门是珠江的主要泄洪通道之一,径流分配居珠江三角洲八大口门之首。利用磨刀门1977年地形(大规模整治前)和2003年的地形,通过ECOMSED模型模拟了磨刀门海域洪枯季节水动力场,对潮流、余流、潮能通量特性进行了对比,发现整治后磨刀门水动力强度加大,而且流速滩槽分异明显,余流场与落潮流方向一致。20世纪70年代,余流自口门出来后在内海区右偏,现在磨刀门水道余流偏向西部浅滩;潮能通量密度加大,滩槽分布差异明显。  相似文献   

随机激励下非线性海洋结构物响应分析方法研究进展   总被引：1，自引：0，他引：1  

王迎光  谭家华 《海洋工程》2007,25(4):112-119

对在随机载荷作用下非线性海洋结构物的运动响应分析的各种方法进行了综述,对有些方法的基本原理做了阐述,并指出一些最新的研究进展和今后进一步研究的方向。  相似文献   

质点-网格海冰模式在渤海的数值预报试验     

刘煜  白珊  刘钦政  吴辉碇 《海洋预报》2005,22(Z1):35-43

在海冰动力学和热力学的研究基础上,开发应用于渤海的质点-网格海冰模式.该模式采用质点-网格法,有效地避免了传统海冰模式的数值扩散问题.该模式采用冰厚分布函数取代传统渤海业务海冰预报模式中平整冰、堆积冰和开阔水的三类海冰分型.应用质点-网格海冰模式对2003年～2004年冬季渤海冰情进行了业务化逐日数值预报试验,并对预报结果进行统计检验和分析比较.  相似文献   

南海西部断裂系研究及其物理模拟实验证据   总被引：3，自引：1，他引：3  

孙龙涛  孙珍  詹文欢  孙宗勋  赵明辉  夏少红 《海洋学报》2006,28(3):64-71

南海西部断裂系是由四条典型的走滑断裂所组成的断裂系统,是南海扩张的西部边界.此断裂系主要是在白垩纪以来的印-藏碰撞、新生代印支挤出和南海扩张的共同作用下形成的.通过模拟实验,探讨此断裂系的成因、演化过程,认识到此断裂系经历了五期构造运动.  相似文献   

Green water overtopping analyzed with a SPH model   总被引：3，自引：0，他引：3  

M. Gmez-Gesteira  D. Cerqueiro  C. Crespo  R.A. Dalrymple 《Ocean Engineering》2005,32(2):651-238

Wave overtopping on the decks of offshore platforms and ships can cause severe damage due to the high forces generated by the water. This phenomenon is analyzed within the framework of the Smoothed Particle Hydrodynamics (SPH) method. The presence of a fixed horizontal deck above the mean water level modifies strongly the wave kinematics. In particular, the flow in the wave crest is split into two, showing a different behavior above and below the deck. Numerical results generated by the SPH method are compared to laboratory experiments. The formation of a jet in the rear of the deck after overtopping is observed under extreme conditions.  相似文献   

塘沽海区海底地形的SAR影像仿真与反演研究   总被引：1，自引：0，他引：1  

夏长水  袁业立 《海洋科学进展》2003,21(4):437-445

利用袁业立、金梅兵(1997)提出的海底地形SAR影像仿真与反演模型，对渤海塘沽海区的一张Radarsat SAR影像进行了仿真和水深反演研究。研究结果表明：仿真影像与真实SAR影像基本吻合，反演水深与实际水深也有较好的一致性；进一步证实了袁业立(1997)SAR成像机理的正确性和在中国近海利用SAR影像进行浅海水深探测的可行性。  相似文献   

Fully nonlinear numerical wave tank (NWT) simulations and wave run-up prediction around 3-D structures     

J. -C. Park  M. -H. Kim  H. Miyata  H. -H. Chun 《Ocean Engineering》2003,30(15):1969-1996

A finite-difference scheme and a modified marker-and-cell (MAC) algorithm have been developed to investigate the interactions of fully nonlinear waves with two- or three-dimensional structures of arbitrary shape. The Navier–Stokes (NS) and continuity equations are solved in the computational domain and the boundary values are updated at each time step by the finite-difference time-marching scheme in the framework of a rectangular coordinate system. The fully nonlinear kinematic free-surface condition is implemented by the marker-density function (MDF) technique developed for two fluid layers.To demonstrate the capability and accuracy of the present method, the numerical simulation of backstep flows with free-surface, and the numerical tests of the MDF technique with limit functions are conducted. The 3D program was then applied to nonlinear wave interactions with conical gravity platforms of circular and octagonal cross-sections. The numerical prediction of maximum wave run-up on arctic structures is compared with the prediction of the Shore Protection Manual (SPM) method and those of linear and second-order diffraction analyses based on potential theory and boundary element method (BEM). Through this comparison, the effects of non-linearity and viscosity on wave loading and run-up are discussed.  相似文献   

Dynamics and control of a towed underwater vehicle system, part I: model development     

B. Buckham  M. Nahon  M. Seto  X. Zhao  C. Lambert 《Ocean Engineering》2003,30(4):82-470

Autonomous vehicles are being developed to replace the conventional, manned surface vehicles that tow mine hunting towed platforms. While a wide body of work exists that describes numerical models of towed systems, they usually include relatively simple models of the towed bodies and neglect the dynamics of the towing vehicle. For systems in which the mass of the towing vehicle is comparable to that of the towed vehicle, it becomes important to consider the dynamics of both vehicles. In this work, we describe the development of a numerical model that accurately captures the dynamics of these new mine hunting systems. We use a lumped mass approximation for the towcable and couple this model to non-linear numerical models of an autonomous surface vehicle and an actively controlled towfish. Within the dynamics models of the two vehicles, we include non-linear controllers to allow accurate maneuvering of the towed system.  相似文献   

地下水封石油洞库渗流场的数值分析   总被引：2，自引：0，他引：2  

刘贯群  韩曼  宋涛  陈浩 《中国海洋大学学报(自然科学版)》2007,37(5):819-824

对研究区水文地质条件和地下水封石油洞库、水幕系统进行了概化,利用Visual MODFLOW软件,建立了某地下水封石油洞库无水幕和有水幕条件下的三维地下水数值模拟模型,模拟了地下水封石油洞库区的渗流场。利用所建模型预报了2种条件下涌入地下水封石油洞库的涌水量、区域地下水降落漏斗扩展情况及洞库上方地下水位变化情况等。由预测结果可知,2种条件下洞库涌水量均逐渐减小并趋于稳定,而有水幕条件下的地下漏斗扩展范围和速度均比无水幕条件小;在洞库开挖初期水幕作用较小,随时间延长作用愈加明显,因此水幕系统在保证地下水封石油洞库的储油安全和保护周围地下水资源方面都起到重要作用。  相似文献   

用样条函数计算结果研究冲绳海槽热源机制     

姜效典  王硕儒 《海洋与湖沼》1996,27(4):394-399

对冲绳海槽１９８４－１９９０年的实测热流值，利用数字滤波方法计算，得到反映该区深部地壳热状态的区域热流值为８０－１６０ｍＷ／ｍ＾２，用Ｂ样条函数法对其作数值模拟，计算出海槽地温场模式，并以此研究冲绳海槽海底高热流的形成机制，得出冲绳海槽热流值的区域性变化与綦中地质构造格局呈正相关，高热流是该区现代构造活动所致，其明显特征是地壳减薄，地幔上拱等结论。  相似文献