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石油泄漏事件的发生，石油羽流在自然环境中的行为已经成为一个中心问题。 在北卡罗来纳州大学流体实验室进行的实验表明，浮力羽流可以被困在水下的强密度分层区域。该项目将探索导致水下捕获多相羽流的机制，如正在进行的海湾泄漏中形成的羽流。 具体来说，该项目将侧重于在密度分层流设施的流体动力学实验在流体实验室，以更好地量化湍流混合，强烈的环境分层，羽浮力，并使用表面活性剂（分散剂）在创建水下捕获羽流的综合作用。 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，内波和剪切的影响下，与目前的泄漏羽行为。 这种理论和实验研究的智力价值包括开发一个基准模型的实际油羽分布，停留时间，表面与次表面的石油馏分。 这项研究的更广泛影响将涉及与直接从事海湾漏油工作的其他团体传播研究结果，包括收集地下卷流分布数据的团体。 此外，PI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泄漏情况。 该研究项目还将涉及两名本科生研究人员的教育，并为高中生创造新的外展机会，让他们参与到生物流体实验室中来。

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.