CAREER: On The Hydrodynamics of River Ice

河冰引发了许多灾害，如洪水、冲刷、冰塞和河岸侵蚀。了解这种流动将带来新的缓解措施和预防溪流和河流灾害的方法。然而，这个问题非常复杂，因为它需要在大的空间尺度上获得湍流数据，从河床宏观粗糙度水平到整个河道平台（千米）。拟议的项目将使用实地测量，理论分析和数值模拟作为一个整体的方法来理解控制河流冰过程的关键因素。该提案的教育计划侧重于与红河守护者、ND EPSCoR办公室和美国地质勘探局北达科他州水科学中心的三方合作，为当地K-12学生和教师提供无障碍的科学活动。这些教育活动旨在激发K-12学生对冬季水力学的兴趣。此外，还将举办一系列研讨会和讲习班，向公众和当局宣传冰流的重要性。该提案旨在整合研究和教育活动，即冰流项目，该项目基于冰层覆盖决定了冬季河流湍流特征的理念。提出的研究的一个独特贡献是发展了一种理论方法来研究冰覆盖对曲流河流河床剪切应力的影响。虽然以前在实验室环境中研究过河床剪切应力的分布，但很少在冲积河道中进行研究。提出的工作的另一个核心新颖之处是一个在冰覆盖的河流中跨流动量转移的模型。通过现场测量和数值模拟，该模型将揭示冰覆盖下横流动量传递与三维结构之间的联系。PI开发的最先进的大涡模拟数值框架是分析冲积河道粗糙度尺度上冰流的重要工具。本文提出的LES模型将作为一个工具，在大的时空差异尺度上研究冰盖的水动力影响。因此，提议的项目有可能改变目前主要基于经验关系的工程实践。该项目由流体动力学计划和建立计划刺激竞争研究（EPSCoR）计划共同资助。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

River ice drives many disasters, such as flooding, scour, ice jams, and bank erosion. Understanding this flow will lead to new mitigation measures and prevention methods for disasters in streams and rivers. However, this problem is very complex because it requires obtaining turbulent flow data at a large disparity in spatial scales, from the level of macro-roughness on the channel bed to the entire channel planform (kilometers). The proposed project will use field measurement, theoretical analysis, and numerical simulation as a holistic approach to understanding the key factors that govern the river ice processes. This proposal's educational plan focuses on the three-prong collaborations with the Red River Keepers, the ND EPSCoR Office, and the USGS North Dakota Water Science Center to provide accessible scientific activities for local K-12 students and teachers. These educational activities are aimed at kindling the interests of K-12 students in winter hydraulics. Furthermore, a series of seminars and workshops will be organized to inform the general public and the authorities about the importance of icy flows.This proposal aims to integrate research and educational activities, the Ice-Flows project, based on the idea that ice coverage dictates the turbulent flow characteristics of rivers in winter. One unique contribution of the proposed research is developing a theoretical approach to investigate the impacts of ice coverage on bed shear stress in meandering rivers. While the distribution of bed shear stress has been studied before in laboratory settings, it has rarely been studied in alluvial channels. Another core novelty of the proposed work is a model for cross-stream momentum transfer in ice-covered rivers. Using field measurement and numerical simulation, the proposed model will reveal the link between the cross-stream momentum transfer and the three-dimensional structure under ice coverage. The PI's development of a state-of-the-art numerical framework for Large Eddy Simulation is the essential tool to analyze icy flows at roughness scales for alluvial channels. The proposed LES model will be used as a tool to investigate the hydrodynamic impacts of ice cover at a large disparity of spatial and temporal scales. Therefore, the proposed project has the potential to transform the current engineering practices, which have been primarily based on empirical relationships.This project is jointly funded by Fluid Dynamics program and the Established Program to Stimulate Competitive Research (EPSCoR) program.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.