CAREER: Advancing Nearshore Circulation Modeling

这个海岸工程研究和教育的综合计划将强调近岸环流模型。两个新的（三维）、时变、非流体静力、大涡模拟（LES）冲浪带模型将用于更好地理解三个重要近岸过程的影响：1)平均底流；2)岸流不稳定性；3)离岸质量输运在离岸流和潜流之间的划分。模型的校准将通过与陆军工程兵团、长岸沉积物运输设施（LSTF）收集的实验室测量数据、最近和正在进行的北卡罗莱纳州达克、佛罗里达州代托纳海滩的现场实验数据以及NCEX等计划中的实验数据进行比较来实现。六个特定的假设将通过模型、实验室和现场数据进行测试。第一个新模型是相位平均模型，它检查了与深度相关的、低频的、近岸洋流对冲浪区破碎波浪的响应。该模型的计算速度比其他类似的规范更快，可用于研究非定常流中平均水流和时间平均下流效应的剪切不稳定性。第二个新模型是基于流体体积（VOF）算法，并在LES近似中模拟冲浪区的单个破波事件。该模型可用于检验个别破波效应，但计算速度较慢，因为解决泊松方程的方法更为复杂，而且需要更小的时间步长来捕捉与破波引起的湍流相关的更高频率波动。预计这些新模型将有助于提高近岸流的预测能力。描述了五种具体的教育整合活动。这包括：1)指导研究生的论文设计；2)指导土木工程专业学生的高级项目；3)开设一门新的本科课程，将海岸工程引入土木工程专业；4)与工程专业以外的学生合作开展近岸科学和公共信息项目，5)通过学习（然后教授）海岸工程的高级课程来加强自己的继续教育。

ABSTRACTPI/Institution: Slinn/UF-G Proposal No: OCE-0239642 This integrated plan for research and education in Coastal Engineering will emphasize nearshore circulation modeling. Two new (three-dimensional (3-D), time-dependent, non-hydrostatic, large-eddy simulation (LES) surf zone models will be used to gain improved understanding of effects of three important nearshore processes: 1) Mean undertow; 2) Along-shore current instabilities; and 3) Partitioning of offshore mass transport between rip currents and undertow. Calibration of the models will be achieved by comparison with laboratory measurements collected at the Army Corps of Engineers, Long-Shore Sediment Transport Facility (LSTF) and with data from recent and ongoing field experiments at Duck, North Carolina, Daytona Beach, Florida, and from planned experiments such as NCEX. Six specific hypotheses will be tested with the models, lab, and field data. The first new model is a phase-averaged model and examines the depth-dependent, low-frequency, nearshore current response to breaking waves in the surf zone. This model is faster computationally than other similar codes and can be used to study shear instabilities of the mean current and time-averaged effects of the undertow in unsteady flows. The second new model is based on the Volume of Fluid (VOF) algorithm and simulates the individual wave breaking events in the surf zone within the LES approximations. This model can be used to examine individual wave-breaking effects but it is slower computationally, because of the more complex methodology for solving the Poisson equation and because smaller time steps are required to capture higher frequency fluctuations associated with turbulent flow caused by breaking waves. It is anticipated these new models will help the field converge towards improved predictive capabilities for near shore flow. Five specific educational integration activities are described. These include: 1) guiding graduate students on their thesis projects; 2) supervising senior projects for Civil Engineering students, 3) developing a new under-graduate course introducing Coastal Engineering to Civil Engineering majors; 4) collaborating with students from outside of engineering on nearshore science and public information projects, and 5) enhancing my own continuing education by taking (and then teaching) advanced courses in Coastal Engineering.