【作者】 余枫；

【导师】 尹勇；

【作者基本信息】 大连海事大学 ， 交通信息工程及控制， 2010， 博士

【摘要】 海上搜救模拟器可用于搜救人员培训与模拟演习,最终达到检验各级搜救中心编制的海上搜救应急预案、检验搜救计划、完成海上搜救辅助决策以及搜救后评估的目的,提高海上人命救助水平。海上溢油处理模块及其实时仿真和三维可视化是海上搜救模拟器的重要组成部分。本文通过对近海划定海域潮流数值模拟和对溢油数学模型的研究,提出了近海溢油的实时仿真和三维可视化算法。作者采用C++语言,基于Visual Studio 2005和Open Scene Graph (OSG) 2.8视景开发环境,实现了对近海划定海域溢油运动的实时仿真和三维可视化。本文的主要工作总结为以下三个方面：1、研究了现有的潮流数值计算算法,划定一片近海海域,并根据其潮波特性来模拟它的潮流场。在数学模型方面本文采用Leendertse J. J.提出的一种二维单层流体力学数学模型来模拟近海潮流,并采用隐式方向交替法进行差分离散。首先在生成的大规模海面场景的基础上进行近海潮流数值计算,从而得到划定海域每个时刻的潮流场。2、对近海溢油的运动过程进行了实时仿真。本文通过研究现有溢油数学模型,实现了海面油膜的扩展、漂移、蒸发和乳化的组合计算,得到了每个时刻油膜的运动参数。在溢油初期,油膜自身扩展采用Fay扩展模型,直至油膜达到最大面积；油膜漂移、蒸发和乳化计算自溢油发生后就一直进行。3、提出一种新的海面溢油三维可视化算法。本文结合海浪的真实感绘制算法,采用OSG的纹理烘焙技术将溢油动态数据绑定到一张纹理图片,再利用平面折射技术将其映射到海面上,从而形象、直观地实现了油膜在海面扩散过程的可视化。最后制定了油与围油栏、油与小岛的碰撞检测算法,实现了油被围油栏拦截过程和油沿小岛岸线运动的仿真和三维可视化。更多还原

【Abstract】 The training using the Marine Search and Rescue Simulator can enhance the flexibility and the collaborative ability of each maritime department while searching and rescuing, it also can improve the emergency pre-scheme, search and rescue plan, computer-aided SAR decision-making support system, evaluation system of SAR established by each level Rescue Coordination Center. The simulation and 3D visualization in real-time of the oil spill on the sea is an important component of Marine Search and Rescue Simulator.On the basis of researching tidal current numerical simulation and oil spill prediction, the simulation and 3D visualization of oil spill are realized in real-time by using C++Language under the Visual Studio 2005 and Open Scene Graph 2.8 in this dissertation. The primary research contents and contributions of this dissertation are summarized as follows:1. A numerical calculation method for the mathematical model of tidal current is proposed. The 2D tidal hydrodynamic models simplified from 3D models exactly show the tidal characters of coast area. By studing present tidal current numerical calculation algorithms, a simplified 2D model is adopted to simulate tidal current in selected coast area firstly. Then, an alternating direction implicit method is used to discrete the 2D model. Finally, the tidal velocity of each point is obtained by tidal current numerical calculation.2. Offshore oil spill dynamic simulation is realized in real-time. Research of oil spill based on present mathematical models, the calculations of oil spread, drift, evaporation and emulsification models are realized, and the oil movement parameters are obtained. From the beginning of spill to the breaking of oil, the FAY spread model is adopted to simulate the spread course of oil, and drift, evaporation and emulsification models are adopted in whole movement course of oil.3. A new 3D visualization algorithm of oil spill is proposed. On the basis of studing the realistic rendering algorithm of ocean wave, a 3D visualization method of oil spill is proposed after analyzing the related theory and technology. Using the Rendering to Texture technique of OSG, a dynamic texture of oil spill trajectory is generated. Then, using the technique of Planar Refraction Map, the dynamic texture is projected to ocean surface in fragment shader. When search and rescue ships come, after deploying oil containment booms, a collision detection algorithm is used to realize the 3D visualization of intercepting scene. The 3D visualization scenes include oil being intercepted by the containment booms and it moving along an island. The 3D visualization results of these scenes are satisfying.更多还原