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

该项目的目标是显著提高在三维海岸和河口环境中准确预测沉积物运输和海底形态的能力。为了实现这一目标，将开发、分析和实施最先进的波、流、沉积物输运和床形态完全耦合的算法。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处理表现出广泛的空间和时间尺度的相互依存过程的准确和有效的耦合。既包括流体运动本身，也包括流体和床层运动之间。我们将基于不连续Galerkin有限元方法开发各种过程的鲁棒性和高度并行化算法，并仔细研究这些算法的耦合，以保持数值精度、效率和沉积物和流体相的局部质量守恒。研究和预测海岸带的形态动力学需要对风、波浪、海流、沉积物运输以及最终由于这些过程而产生的海底形态变化有详细的了解。河床沉积物的侵蚀和沉积可能对沿海人口、基础设施和环境产生重大的有害影响。例如，在卡特里娜飓风期间，在风暴期间发生的四个主要堤坝的溃决是由冲刷引起的基础诱发的失败造成的。沉积物的运输与沿海地区的一些其他问题密切相关，包括水质和有关的生态问题、海滩和海岸线的侵蚀以及通过疏浚活动维持航道和港口。准确估计预期的泥沙输送和河床形态变化对沿海和河口环境的长期规划和管理有很大帮助。在这个项目中，研究者将开发一个完全耦合的波、流、沙输运和床形态模型系统。这样一个系统将大大提高在沿海和河口环境中准确预测沉积物运输和海底形态的能力。通过这项研究，人们将对沿海地区的水动力、运输和形态动力过程之间的复杂相互关系有一个更好的科学理解，这将有助于做出更明智的决策，从而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计算基础设施，可用于计算建模领域的许多其他应用程序。此外，根据该项目开发的技术将分发给NOAA和美国陆军工程兵团等政府机构。

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.