考虑岸滩附着作用的近岸溢油漂移介观数值模拟方法

Oil spill accidents would cause serious pollution and damage to water and ecological environment. It is crucial to thoroughly investigate the oil spill transport model and the adhering effect of shorelines in exploring the mechanism of the movement of oil film. However, the existing research were mainly concentrated on the oil spill models based on the marine environment rather than the tidal reach or nearshore area. The proposed project is going to derive a two-phase two-layer fluid model to simulate oil expansion. Based on the drift-diffusion theory of oil particle model and the mesoscopic lattice Boltzmann method (LBM), we also plan to develop a novel boundary condition for the adhering effect of shorelines, and set up its corresponding two-dimensional oil spill drift-diffusion model to study its expanding and transport processes, involving the influence from wave, current and tide. In order to reduce computational cost and increase model efficiency in simulating large-scale problem in practice for long periods, the characteristics of LBM for parallel computing and the graphic process unit technique would be used. Successful completion of the proposed project will make contribution to the improvement of the lattice Boltzmann method and will also provide technical support for decision making in case of oil spill emergency.

溢油事故会对水环境和水生态造成严重的污染和危害，深入讨论溢油漂移扩散模型和岸滩对油膜的附着作用对研究油膜在水面扩展和漂移过程具有重要意义。但现有研究主要集中在基于海洋环境溢油漂移模型，对近岸水域如感潮河段、河口油膜迁移过程及岸滩附着作用的研究较少。本项目拟建立两相双层流体模型模拟溢油扩展过程；以油粒子扩散漂移理论和浅水格子Boltzmann介观方法为基础，开发全新的油膜岸滩附着作用边界条件，提出考虑岸滩附着影响的近岸溢油扩展和漂移扩散模拟方法。研究开发水流、波浪、潮汐综合条件下的溢油模型，真实还原其物理过程并提高计算精度。为了满足长时间、广水域的计算要求，模型利用格子Boltzmann方法适合并行运算的特点，采用基于图形处理器的高性能计算技术。本研究在理论上可促进格子Boltzmann方法的改进和完善，而且为突发溢油事故模拟和应急方案的制定提供技术支持，具有较好的实际应用价值。

近年来由于人类活动的影响，许多地表水体和海洋受到污染而造成水质恶化，这其中包括大量的石油泄漏等突发性水污染事件。溢油事故会对水环境和水生态造成严重的污染和危害，深入讨论在水动力作用下溢油漂移扩散模型和岸滩对油膜的附着作用对研究油膜在水面扩展和漂移过程具有重要意义。已有的模型对于溢油与岸边作用的模拟进行了不同程度的概化，对于吸附机制的研究尚不成熟。因此，有必要开发完善溢油模型对近岸溢油扩展漂移规律进行深入研究，考虑复杂水动力及岸滩对溢油运动的作用，预测其扩散的范围，为溢油事故应急方案的制定、处理方法的选择提供技术支持，减小对生态环境的破坏。本研究利用了格子Boltzmann方法具有的欧拉和拉格朗日双重属性，提出了基于两相双层流体的溢油模拟方法和通过歪理处理格式考虑岸滩附着的边界条件，模拟水面油膜输移过程。通过建立二维格子Boltzmann波流和潮汐水动力模型，耦合油粒子模型，采用GPU并行计算技术，高效的模拟水面油膜漂移过程，分析波浪和潮汐等因素作用下油膜的运动规律，并将该溢油模型应用于典型水域。本研究从介观的角度建立准确、高效的波流耦合模型和溢油模型，对于溢油输移规律的探索具有重要的科学意义。此外，研究成果还可以对优化溢油污染治理方案提供相应的技术支持。