RAPID: Multi-phase Buoyant Plumes in Stratified Water Study relevant to Oil Spill Implications for the Gulf oil spill distribution

随着最近墨西哥湾深水地平线漏油事件的发生，石油羽流在自然环境中的行为成为一个中心问题。在北卡罗来纳大学流体实验室进行的实验表明，浮力羽流可以被困在密度层结强烈的地区的水下。该项目将探索导致水下捕获多相羽流的机制，就像正在进行的墨西哥湾漏油事件中形成的那样。具体地说，该项目将侧重于在北卡罗来纳大学流体实验室的密度分层流动设施中进行流体动力学实验，以更好地量化湍流混合、强烈环境层结、羽流浮力和表面活性剂(分散剂)的使用在创建水下捕获羽流过程中的综合作用。将开发理论闭合模型来解释实验并指导现场研究。进一步的研究将包括直接的数值模拟，以探索高温、高压、内波和与此次漏油相关的剪切影响下的羽流行为。这项理论和实验研究的智力价值包括开发实际油羽分布、停留时间以及地面和地下石油馏分的基准模型。这项研究的更广泛影响将涉及与其他直接研究墨西哥湾漏油事件的小组一起传播结果，包括那些收集地下烟羽分布数据的小组。此外，PIS将向石油行业和EPA等监管机构提供结果，以帮助了解当前和未来的漏油情况。该研究项目还将涉及两名本科研究人员的教育，并为高中生参与北卡罗来纳大学流体实验室创造新的外展机会。

With the recent Deepwater Horizon oil spill in the Gulf of Mexico, the behavior of oil plumes in the natural environment has come become a central question. Experiments performed in the University of North Carolina (UNC) Fluids Laboratory have shown that buoyant plumes can be trapped underwater at regions of strong density stratification. This project will explore the mechanisms leading to underwater trapping of multi-phase plumes like those forming in the ongoing Gulf spill. Specifically, the project will focus on fluid dynamics experiments in the density-stratified flow facility in the UNC Fluids Lab to better quantify the combined roles of turbulent mixing, strong ambient stratifications, plume buoyancy, and use of surfactants (dispersants) in creating under water trapped plumes. Theoretical closure models will be developed to interpret the experiments and guide field studies. Further research will include direct numerical simulations to explore plume behavior under the effects of high temperature, high pressure, internal waves, and shear associated with this current spill. The intellectual merit of this theoretical and experimental research includes developing a benchmarked model for actual oil plume distribution, residence time, and surface versus sub-surface oil fractions. Broader impacts of the research will involve disseminating results with other groups directly working on the Gulf Oil Spill, including those collecting data on the subsurface plume distribution. Additionally, the PIs will make results available to the petroleum industry and regulatory agencies such as EPA to assist in the understanding of current and future spills. The research project will also involve the education of two undergraduate researchers and create new outreach opportunities for high school students to participate in the UNC Fluids Lab.