Collaborative Research: Computational Methods for Coupled Wave, Current, Sediment Transport and Morphological Evolution

该项目的目标是大大提高准确预报三维海岸和河口环境中沉积物迁移和海底形态的能力。为了实现这一目标，将开发、分析和实施关于完全耦合波、流、泥沙输运和河床形态的最新算法。这一系统的发展将需要对所涉及的各种过程的紧密耦合性质有更好的数学和物理理解。此外，它还需要计算策略来解决相互依赖的过程之间的准确和有效的耦合，这些过程表现出广泛的空间和时间尺度--既在流体运动本身内，也在流体和床面运动之间。基于不连续Galerkin有限元方法，将开发各种过程的稳健和高度可并行化的算法，并将仔细研究这些算法的耦合，以保持数值精度、效率以及沉积物和流体相的局部质量守恒。研究和预测海岸带的地貌动力学需要详细了解风、波、流、泥沙的输运，并最终了解这些过程导致的海床形态变化。河床沉积物的侵蚀和淤积可能对沿海人口、基础设施和环境产生重大有害影响。例如，在卡特里娜飓风期间，风暴期间发生的四个主要堤坝堤坝是由冲刷引起的地基破坏造成的。泥沙的输送与海岸带的其他一些问题密切相关，包括水质和相关的生态问题、海滩和海岸线的侵蚀，以及通过疏浚活动维护航道和港口。准确估计预期的泥沙输送和河床形态变化，对海岸和河口环境的长期规划和管理大有裨益。在这个项目中，研究人员将开发一个完全耦合的波浪、水流、泥沙输运和河床形态模型系统。这一系统将大大提高准确预测海岸和河口环境中泥沙运移和海底形态的能力。通过这项研究，将对沿海地区水动力、运输和地貌动力学过程之间的复杂相互关系有更好的科学了解，这将导致更知情的决策，这将有助于保护沿海人口和基础设施。该项目开发的软件还将提供一个计算基础设施，可用于计算建模领域内的许多其他应用。此外，根据该项目开发的技术将传播给美国国家海洋和大气管理局和美国陆军工程兵部队等政府机构。

The goal of this project is to significantly advance the capability to accurately predict sediment transport and seabed morphology in three-dimensional coastal and estuarine environments. To achieve this goal, state-of-the-art algorithms for fully coupled wave, current, sediment transport and bed morphology will be developed, analyzed, and implemented. The development of this system will require a better mathematical and physical understanding of the tightly coupled nature of the various processes involved. In addition, it will require computational strategies which address the accurate and efficient coupling of interdependent processes that exhibit a wide range of spatial and temporal scales?both within the fluid motion itself and between the fluid and bed motion. Robust and highly parallelizable algorithms for the various processes will be developed based on discontinuous Galerkin finite element methods, and the coupling of these algorithms will be carefully investigated in order to maintain numerical accuracy, efficiency, and local mass conservation of sediment and fluid phases.Studying and predicting the morphodynamics of the coastal zone requires a detailed knowledge of winds, waves, currents, sediment transport and, ultimately, the resulting morphological changes of the seabed that occur as a result of these processes. The erosion and deposition of bed sediment can have a major detrimental impact on the coastal population, infrastructure and environment. For example, during Hurricane Katrina, four major levee breeches that occurred during the storm were a result of foundation-induced failures caused by scour. The transport of sediment is closely tied to a number of other issues in the coastal zone, including water quality and related ecological concerns, beach and shoreline erosion, and the maintenance of navigation channels and harbors through dredging activities.Accurate estimates of expected sediment transport and bed morphological changes can aid greatly in the long-range planning and management of coastal and estuarine environments. In this project, the investigators will develop a fully coupled wave, current, sediment transport and bed morphology model system. Such a system will significantly advance the capability to accurately predict sediment transport and seabed morphology in coastal and estuarine environments.From this research, a better scientific understanding of the complex interrelations among hydrodynamic, transport and morphodynamic processes in the coastal zone will emerge, which can lead to more informed decision-making that will help protect the coastal population and infrastructure. The developed software of the project will also provide a computational infrastructure that can be used in many other applications within the area of computational modeling. Furthermore, the technology developed under this project will be disseminated to government agencies such as NOAA and the US Army Corps of Engineers.