EAR-PF: The Mechanics of Turbulence and Sediment Transport: Physically-Based Numerical Modeling of Flow, Sediment and Bed Evolution in the Bedrock Canyons

EAR-PF：湍流和沉积物输送的力学：基岩峡谷中流动、沉积物和河床演化的基于物理的数值模拟

• 批准号: 1806205
• 负责人: Laura Alvarez
• 金额: $ 17.4万
• 依托单位: Alvarez Laura V
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-01-01 至 2021-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1806205&HistoricalAwards=false
• 关键词: EAR; PF; Mechanics; Turbulence; Sediment

Dr. Laura V. Alvarez has been awarded an NSF Earth Sciences Postdoctoral Fellowship to carry out a research and education plan at the University of Oklahoma and Simon Fraser University. The proposed work will make substantial contributions to our capability to numerically understand and predict the physical phenomena that control sediment transport and morphodynamic evolution of river networks. Gains in the knowledge of the role played by macro-turbulence events in sediment dynamics will allow us to obtain a deeper understanding of what determines the geomorphologic changes and will lead to the development of more efficient models.This model can also serve to investigate to what extent information obtained from well-controlled experiments and numerical simulations conducted at laboratory scale can be used to understand the physics of sediment transport at larger scales and to provide predictions about river network changes. The fellow will engage education and outreach by developing a six-week summer course in fluvial modeling, integrating many of the proposed research experiments.Eddy resolving three-dimensional simulations combined with field and laboratory observations allow elucidation of key elements of fluid dynamics and sediment transport in fluvial environments. These models can resolve the time-dependent, energetically important, turbulent structures of the flow capturing the interactions between these eddies and the loose bed boundaries where sediment entrainment and deposition can occur. This research study proposes a compelling strategy for applying state-of-the-art computational fluid mechanics to the study of sediment transport and morphodynamic processes in fluvial systems. The main objective of the proposed research is the development and testing of a fully three-dimensional turbulence resolving model using Dettached Eddy Simulation techniques that can simulate turbulent flows under a broad range of spatial and temporal scales and their effect on sediment transport, entrainment and deposition and channel/river reach evolution. The numerical model will then be used to (1) understand the role played by the plunging flows, secondary flows and velocity inversions on sediment transport, entrainment and deposition in river reaches and (2) explain morphodynamic changes based on the dynamics of the macro-turbulence effects and velocity redistribution inside the river reach.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.

Laura V. Alvarez博士被授予NSF地球科学博士后研究金，以在俄克拉荷马大学和西蒙·弗雷泽大学（Simon Fraser University）进行研究和教育计划。拟议的工作将为我们的能力做出重大贡献，即在数值上理解和预测控制沉积物运输和河网络形态动力学演变的物理现象。在对沉积物动力学中宏扰动事件所扮演的角色所扮演的角色所扮演的角色的了解方面，我们能够深入了解什么决定了地貌学变化，并将导致更有效的模型的发展。该模型还可以调查从何种程度上获得从良好的实验和数字模拟在实验室尺度上进行较大的量表的信息，以便在实验室尺度上进行较大的量表，从而可以使用较大的量表来了解量表的量表，从而可以使用量表和量表的变化。该研究员将通过开发一个为期六周的河流建模课程，整合许多拟议的研究实验，从而吸引教育和外展。这些模型可以解决时间依赖性，能量重要的，湍流的结构，从而捕获可能发生沉积物夹带和沉积物之间的这些涡流与松散的床边界之间的相互作用。这项研究提出了一种令人信服的策略，用于将最先进的计算流体力学应用于河流系统中的沉积物传输和形态动力学过程。拟议研究的主要目的是使用可驱动的涡流模拟技术开发和测试完全三维的湍流解析模型，该技术可以在广泛的空间和时间尺度下模拟湍流及其对沉积物传输，夹带和沉积以及沉积以及河流/河流的影响。然后，数值模型将用于（1）了解跌落流动，次要流动和速度反转在河流中的沉积物传输，夹带和沉积的速度反转所起的作用，（2）基于宏观扰动的效果和速度范围内的批准，解释了形态动力学的变化。基金会的智力优点和更广泛的影响审查标准。