Japan STA Program: Turbulence Structure and Sediment- Transport Field near a Flow Obstruction at the Bed of a Hydraulically Rough Turbulent Boundary Layer

日本 STA 计划：水力粗糙湍流边界层底部流动障碍附近的湍流结构和沉积物输送场

• 批准号: 9803854
• 负责人: Mark Schmeeckle
• 金额: $ 1.19万
• 依托单位: Fellowships
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-01 至 2000-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9803854&HistoricalAwards=false
• 关键词: Japan; STA; Program; Turbulence; Structure

Schmeeckle 9803854 This award supports a 24 month Science and Technology Agency of Japan (STA) Postdoctoral Fellowship for Dr. Mark Schmeeckle at the Civil Engineering Research Institute (CERI) in Sapporo, Japan. Dr. Schmeeckle will work with Dr. Hitoshi Baba, General Director, CERI, on a research project entitled "Turbulence Structure and Sediment-transport Field Near a Flow Obstruction at the Bed of a Hydraulically Rough Turbulent Boundary Layer." The scour of sediment from around river structures during flood is a major engineering concern. Such scour can lead to the loss of the structure or expensive repairs. Unfortunately, the prediction of scour is often based on empirical methods with little physical understanding, and even scale models are difficult because it is nearly impossible to accurately scale both the flow and sediment transport fields simultaneously. Previous physically based sediment transport models only considered mean flow conditions in simplified turbulence fields and performed poorly in complex flow conditions such as around river structures. In this study a newly developed model, which directly couples the instantaneous near-bed velocity to the sediment transport field, will be applied to the case of flow around a cylindrical pier. To accomplish this goal, high-frequency measurements of near-bed velocities around the pier will be collected. These velocity measurements will then be used to drive the sediment transport model, and the sediment transport will in turn be used to predict the evolution of the scour profile around the cylinder. Successful completion of this project will result in a physically based understanding of scour around river structures. ***

Schmeeckle 9803854 该奖项为Mark Schmeeckle博士在日本札幌土木工程研究所（CERI）提供为期24个月的日本科学技术厅（STA）博士后奖学金。 Schmeeckle博士将与CERI总干事Hitoshi Baba博士合作开展一个题为“水力粗糙湍流边界层底部流动障碍物附近的湍流结构和沉积物输运场”的研究项目。" 洪水对河道建筑物周围泥沙的冲刷是一个重要的工程问题。 这种冲刷可能导致结构损失或昂贵的维修费用。 不幸的是，冲刷的预测往往是基于经验的方法，几乎没有物理的理解，甚至比例模型是困难的，因为它几乎是不可能的，同时准确地缩放的水流和泥沙输运场。 以往的物理泥沙输运模型只考虑了简化湍流场中的平均水流条件，在复杂的水流条件下（如河流结构物周围）表现不佳。 在这项研究中，一个新开发的模型，直接耦合瞬时近床流速的泥沙输运场，将被应用到绕圆柱形桥墩的情况下。 为了实现这一目标，将收集桥墩周围近床流速的高频测量值。 然后，这些速度测量值将用于驱动泥沙输运模型，而泥沙输运又将用于预测圆柱体周围冲刷剖面的演变。 该项目的成功完成将导致对河流结构物周围冲刷的物理基础的理解。 ***