CAREER: Multiphase Sediment Transport Modeling Framework

更好地了解和预测沿海沉积物输运过程的能力对于保护国家沿海资源免受自然灾害和人类影响至关重要。能够准确地预测大规模的海岸过程是依赖于有一个详细的了解小规模的沉积物输运发生在沿着海岸。知识专长：大规模海岸过程的准确预测依赖于对小规模沉积物输运的详细了解。本计画将发展一个三维全耦合多相流大涡模拟（Large-eddy simulation，LES）数值模式框架以模拟泥沙输移。流体-颗粒系统的建模方法利用欧拉-欧拉双流体公式来解决三维多相湍流，并利用欧拉-拉格朗日公式来进一步详细描述颗粒的PDF，适合于海岸沉积物输运的典型的数百万沉积物颗粒。新的框架解决了三维流动湍流，流体颗粒相互作用，颗粒间应力，因此同时模拟推移质和悬移质。它改进了现有的雷诺平均两相模型的集中传输和单相三维LES模型的稀流。该教育计划概述了一个职业目标，通过开发面向少数民族的本科研究和教育计划，建立一支多元化的沿海/海洋工作队伍。研究实习和本科水平的海岸工程课程的发展将促进现有的面向研究生的海岸/海洋学计划和本科工程和科学学生在佛罗里达大学（UF）之间的有效连接。更广泛的影响：保护国家的沿海资源免受自然灾害的影响（例如，飓风）和人类影响，可靠的预测工具，允许长时间和大空间模拟沿海/河口沉积物输运过程是至关重要的。拟议的项目强调利用详细的模型来提供小规模过程的改进参数化，大规模建模者可以进一步利用这些参数化来开发与沿海规划和减灾相关的沿海/河口过程的预测工具。对于这个建立在多元文化基础上的国家来说，建立多元化的劳动力队伍势在必行。海岸/海洋学学科通常涉及减灾和土地保护，这些问题与经济，社区和社会正义有关。因此，确保广泛参与沿海/海洋学专业尤为重要。拟议的本科生研究实习（每年2名非UF少数民族学生和2名UF学生）加入并受益于UF现有的NSF赞助的SEAGEP，致力于增加少数民族学生的数量，以追求学术/职业生涯。针对初中/高中学生和教师的外联工作说明了一个基于“沿海灾害和海滩过程”的主题。它不仅将促进环境素养，而且还将作为一个渠道，向8-12年级的学生介绍一个迷人的科学/工程学科，为他们的高等教育。

OCE-0644497A better understanding and the ability to predict coastal sediment transport processes are important in order to preserve the nation's coastal resources from natural disasters and human impacts. Being able to accurately predict large-scale coastal processes is dependant upon on having a detailed understanding of small-scale sediment transport that takes place along the coast. Intellectual Merit: Accurate prediction of large-scale coastal processes relies on detailed understanding of small-scale sediment transport. This project will develop a 3D fullycoupled multiphase LES (Large-eddy simulation) numerical modeling framework for sediment transport. The modeling approach for fluid-particle system utilizes both Eulerian-Eulerian two-fluid formulation to resolve 3D multiphase turbulent flow and Eulerian-Lagrangian formulation for further detailed PDF description of particles that are suitable for coastal sediment transport typical of millions of sediment particles. The new framework resolves 3D flow turbulence, fluid-particle interactions, inter-granular stresses and hence concurrently models the bedload and suspended load. It improves upon existing Reynolds average two-phase models for concentrated transport and single-phased 3D LES models for dilute flow. The educational plan outlines a career goal to establish a diversified Coastal/Oceanographic work force through developing a minority-oriented undergraduate research and education program. The research internship and the development of the undergraduate-level Coastal Engineering course will facilitate effective connection between the existing graduate-oriented Coastal/Oceanographic Program and undergraduate Engineering and Science students at University of Florida (UF). Broader impact: To preserve the nation's coastal resources from natural disasters (e.g., hurricane) and human impact, reliable predictive tools that allow long-temporal and largespatialsimulation of coastal/estuarine sediment transport processes is vital. The proposed project emphasizes utilizing detailed models to provide improved parameterizations of smallscale processes that can be further utilized by large-scale modelers to develop predictive tools for coastal/estuarine processes relevant to coastal planning and hazard mitigation. Establishing a diversified work force is imperative for this country that has been built upon multiculturalism. Coastal/Oceanographic discipline often deal with hazard mitigation and land preservation, issues that are relevant to economics, communities, and social justice. Hence it is especially vital to ensure broad participation in Coastal/Oceanographic professions. The proposed undergraduate research internship (2 non-UF minority students and 2 UF students per year) joins in and benefits from the existing NSF-sponsored SEAGEP at UF that is committed to increasing the number of minority students to pursue an academic/professional career. The outreach efforts to middle/high school students and teachers illustrate a theme based on "Coastal Hazard and Beach Processes". It will not only promote environmental literacy but also serves as a conduit to introduce to 8-12 grades students a fascinating science/engineering discipline for their higher education.