Collaborative Research: Correlating Large-Scale Visual Structures to Entrainment Mechanisms in Buoyant and Momentum-Driven Plumes

合作研究：将大规模视觉结构与浮力和动量驱动羽流中的夹带机制相关联

• 批准号: 2231781
• 负责人: Alexis Kaminski
• 金额: $ 25万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-12-01 至 2025-11-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2231781&HistoricalAwards=false
• 关键词: Collaborative; Research; Correlating; Large; Scale

This research will explore the development of buoyant plumes, specifically to quantify how physical structures that develop along the plume/ambient interface result from mass transport through an outlet, and how these structures subsequently affect entrainment and mixing. This work will uncover mechanistic differences in plume evolution, depending on source conditions, thus informing transport models to appropriately incorporate physics for these phenomena. This is key to understanding and predicting the fate of nutrients or pollutants from plumes – for example, volcanic ash clouds, discharges into bays or estuaries, and a host of other environmental and industrial flows. While the fluid dynamics community has long acknowledged the range of physical length scales of eddies in turbulent flows, there exists a lack of research regarding how the exterior structure of a plume or jet is linked to the source conditions. Knowledge uncovered through this research will provide robust means for quantifying plume dynamics through image analysis of remotely acquired data. The research will support the training of two graduate students and undergraduate researchers. The research team will develop workshops for local outreach and educational programs, and data from the outreach events will be used in the research mission. Finally, this project will form the basis for a project for a graduate student in the WHOI summer program in Geophysical Fluid Dynamics.Laboratory experiments and direct numerical simulations will be conducted to satisfy two primary objectives. The first goal is to develop techniques to identify and quantify features comprising the plume structure to remotely determine source conditions of industrial or natural plumes from video or photographic recordings. The second goal is to investigate mechanisms of mixing and entrainment at the plume/ambient interface. In laboratory experiments, simultaneous spatio-temporally resolved particle image velocimetry and laser induced fluorescence measurements will be used to quantify the flow field and mass transport, respectively. Time lapse stereo photogrammetry will be used to reconstruct the dynamic three-dimensional outer edge of the plume, from which distributions of the length scales comprising the external structure can be characterized. A complementary suite of direct numerical simulations will be performed in quiescent unstratified and stratified background fluids. The turbulent/non-turbulent interface and the structures driving entrainment and mixing at the plume edges will be identified in the simulation data and subsequently be compared to the laboratory data. This research will enhance our ability to determine source conditions during plume-driven phenomena, including but not limited to volcanic eruptions, forest fires, glacial discharge plumes, undersea dispersion, and disease transmission.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.

这项研究将探索浮力羽流的发展，特别是量化沿着羽流/环境界面发展的物理结构如何由通过出口的质量传输产生，以及这些结构随后如何影响夹带和混合。这项工作将揭示羽流的机械差异。进化，取决于源条件，从而通知传输模型适当地结合这些现象的物理学，这是理解和预测烟羽中营养物或污染物的命运的关键——例如火山灰云，排放到其中。尽管流体动力学界早已认识到湍流中涡流的物理长度尺度范围，但仍缺乏关于羽流或射流的外部结构的研究。通过这项研究发现的知识将为通过远程获取的数据的图像分析来量化羽流动力学提供强有力的方法，该研究将为两名研究生和本科生研究人员的培训提供支持。外展和教育最后，该项目将构成 WHOI 地球物理流体动力学夏季项目研究生项目的基础。将进行实验室实验和直接数值模拟。第一个目标是开发识别和量化羽流结构特征的技术，以便从视频或摄影记录中远程确定工业或自然羽流的源条件。这在实验室实验中，同步时空分辨粒子图像测速和激光诱导荧光测量将分别用于量化流场和质量传输，以重建动态三维。羽流的外边缘，从中可以表征构成外部结构的长度尺度的分布，将在静态非分层和分层背景流体中进行一套互补的直接数值模拟。湍流/非湍流界面以及在羽流边缘驱动夹带和混合的结构将在模拟数据中被识别，并随后与实验室数据进行比较。这项研究将增强我们确定羽流驱动现象期间源条件的能力，包括。但不限于火山爆发、森林火灾、冰川喷流、海底扩散和疾病传播。该奖项是 NSF 的法定使命，并通过使用基金会的智力价值进行评估，被认为值得支持以及更广泛的影响审查标准。