RAPID: Collaborative Research: Multiscale plume modeling of the Deepwater Horizon oil-well blowout for environmental impact assessment and mitigation

RAPID：协作研究：深水地平线油井井喷的多尺度羽流建模，用于环境影响评估和缓解

• 批准号: 1045831
• 负责人: Scott Socolofsky
• 金额: $ 3.74万
• 依托单位: Texas A&M Engineering Experiment Station
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-08-15 至 2012-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1045831&HistoricalAwards=false
• 关键词: RAPID; Collaborative; Research; Multiscale; plume

The subsurface plume from the Deepwater Horizon (DH) accidental oil-well blowout is a complex, layered system of intrusions containing oil, dissolved hydrocarbons, and injected dispersants that will have far-reaching environmental consequences; however, no modeling tools are currently producing highly-resolved predictions of the plume structure and evolution. The goal of this Rapid Response Research Proposal (RAPID) is to develop a three-dimensional, multiscale hydrodynamic model for the DH blowout plume that combines the Reynolds averaged Navier Stokes (RANS) modeling approach with the method of large-eddy simulation (LES). The resulting model platform will be validated to field and laboratory data, will respect the relevant chemistry and thermodynamics of the released oil and natural gas, and will be forced by the measured ambient conditions surrounding the spill. Such a simulation tool is urgently needed to guide field observations, predict the onshore migration and loop-current capture of the spilled oil, assess the effectiveness and potential environment impact of dispersants injected at the source, and to understand the response to this event already measured in the vertical migration of plankton and fish. The validated modeling platform will be developed through complementary laboratory experiments, numerical modeling, and analysis of field data. The laboratory experiments will evaluate the effects of currents as the flow through the plume and pull oil and dissolved constituents into the wake of the plume. The numerical methods will utilize a very large eddy simulation (VLES) to resolve the dominant plume structures in the near field of the blowout plume and will nest this model in a far-field model based on the unsteady RANS approach. Field data from acoustic Doppler current profilers will provide model forcing and validation data and will also be analyzed to understand the role of subsurface plume dynamics on the vertical migration of plankton and fish as also recorded in the ADCP data. Early analysis of this data shows a very rapid shut-down of the diurnal vertical migration pattern at nearby stations shortly after the start of the spill. This is the first documented environmental response to the blowout, and it remains unknown whether this is due to mortality, avoidance, light penetration changes or other processes. The sub-surface plume model developed here will provide detailed predictions of the subsurface plume structure necessary to analyze this environmental response. Intellectual Merit: The primary intellectual merit of the project will be an understanding of the critical physical and chemical processes in an accidental oil-well blowout that lead to the subsurface layered structure of oil and dissolved hydrocarbons in the water column. Important insight will also be gained on the appropriateness of a classical RANS model for predicting the dynamics of the oil and gas intrusions. Broader Impact: Predictions from the model will help guide the collection of observation data in the field and will be applied to understand why plankton and fish in the vicinity of the blowout shut down their vertical migration pattern shortly after the blowout. The model is also needed to predict the transport of oil and injected dispersants throughout the Gulf ecosystem, including onshore and into the loop current and potentially into the Atlantic ocean. Detailed studies of turbulence in multiphase plumes conducted in the later stages of the project will ultimately result in a reliable model framework featuring a zonal RANS-VLES simulation tool applicable to a wide range of environmental applications of multiphase plumes, including CO2 sequestration, lake aeration, and sediment plumes, among others.

深水地平线（DH）意外油井井喷的地下羽流是一个复杂的，分层的侵入系统，含有石油，溶解的碳氢化合物和注入的分散剂，将产生深远的环境影响;然而，目前没有建模工具产生高分辨率的羽流结构和演变的预测。 本快速响应研究建议（RAPID）的目标是开发一个三维的，多尺度的DH井喷羽流的流体动力学模型，结合雷诺平均Navier Stokes（RANS）建模方法与大涡模拟（LES）的方法。 将根据现场和实验室数据对所产生的模型平台进行验证，该平台将考虑释放的石油和天然气的相关化学和热力学，并将受泄漏周围测量的环境条件的影响。 迫切需要这样一种模拟工具来指导现场观测，预测泄漏石油的陆上迁移和环流捕获，评估在源头注入分散剂的有效性和潜在的环境影响，并了解在浮游生物和鱼类垂直迁移中已经测量到的对这一事件的反应。 将通过补充实验室实验、数值模拟和现场数据分析开发经验证的建模平台。 实验室实验将评估水流流经羽流时的影响，并将石油和溶解的成分拉入羽流的尾流。 数值方法将利用一个非常大的涡模拟（VLES）来解决井喷羽流的近场的主要羽流结构，并将嵌套在一个基于非定常RANS方法的远场模型中的模型。 来自声学多普勒海流剖面仪的现场数据将提供模型强迫和验证数据，还将进行分析，以了解地下羽流动态对浮游生物和鱼类垂直迁移的作用，这也记录在ADCP数据中。 对这些数据的早期分析表明，在泄漏开始后不久，附近站点的昼夜垂直迁移模式迅速停止。 这是第一次记录到井喷的环境反应，目前还不清楚这是由于死亡，回避，光穿透变化还是其他过程。 在这里开发的次表层羽流模型将提供详细的预测的次表层羽流结构分析这种环境响应。 智力优势：该项目的主要智力价值将是了解意外井喷中的关键物理和化学过程，这些过程导致石油和溶解在水柱中的碳氢化合物的地下分层结构。 重要的洞察力也将获得一个经典的RANS模型预测石油和天然气入侵的动态的适当性。 更广泛的影响：该模型的预测将有助于指导现场观测数据的收集，并将用于了解井喷附近的浮游生物和鱼类在井喷后不久关闭其垂直迁移模式的原因。 还需要该模型来预测石油和注入的分散剂在整个海湾生态系统中的运输，包括陆上和进入环流，并可能进入大西洋。 在该项目的后期阶段进行的多相羽流中湍流的详细研究将最终产生一个可靠的模型框架，该模型框架具有适用于多相羽流的广泛环境应用的分区RANS-VLES模拟工具，包括CO2封存，湖泊曝气和沉积物羽流等。