CAREER: Intermittency and Two-Fluid Transitions in Pulsed-Power-Driven Magnetized Turbulence

职业：脉冲功率驱动磁化湍流中的间歇性和二流体转变

• 批准号: 2339326
• 负责人: Jack Hare
• 金额: $ 85万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-12-01 至 2028-11-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2339326&HistoricalAwards=false
• 关键词: CAREER; Intermittency; Two; Fluid; Transitions

This award supports a research program to study the physics of a turbulent plasma in the laboratory. Turbulence exists in the fluids that we experience every day. The unpredictability of turbulence limits our forecasting ability for everything from weather to air travel. Turbulence also exists in plasmas - the hot, ionized gases that make up most of the visible Universe. Plasma turbulence plays an important role in a wide range of astrophysical phenomena, from black hole accretion disks to the interstellar medium, where the heating from turbulence enables the formation of organic molecules which are the building blocks of life. Plasma turbulence also limits the performance of potential future fusion energy reactors. This research program will develop a new platform for producing turbulent plasma in the laboratory and new methods for measuring plasma turbulence. The award also supports a substantial effort to develop an open-access plasma laboratory class, which includes designing, building, and testing laboratory experiments that can be easily reproduced by other instructors. If successful, this effort will strengthen the US STEM workforce by spreading plasma physics instruction to a broader range of educational institutions.Just as hydrodynamic turbulence is built from vortices of fluid motions, magnetized plasma turbulence is built from magnetic islands and current sheets, which serve to transfer the magnetic energy between different spatial scales. This project will use an imploding carbon wire-array Z-pinch, driven by the new PUFFIN generator at the Massachusetts Institute of Technology, as a magnetic island merging platform to generate magnetized plasma turbulence. This magnetized plasma turbulence will be in a previously unexplored regime: sustained, highly collisional, with an ion-skin depth between the driving and dissipative scales, and energy approximately equipartitioned between magnetic, thermal, and kinetic. Advanced diagnostics, such as Faraday rotation imaging, Thomson scattering, and imaging refractometry, will be used to study the transition from a laminar to a turbulent plasma. The diagnostics will serve to characterize the evolution of the power-spectrum and intermittent structures above and below the ion skin depth, and the role of an imposed or self-generated mean-field in correlating turbulent structures.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.

该奖项支持一项研究计划，以研究实验室中湍流等离子体的物理学。 我们每天体验到的液体中存在湍流。湍流的不可预测性限制了我们对从天气到航空旅行的所有事物的预测能力。等离子体中也存在湍流 - 构成大部分可见宇宙的热，电离气体。等离子体湍流在从黑洞积聚磁盘到星际介质的各种天体物理现象中起着重要作用，在那里，来自湍流的加热可以形成有机分子，这些分子是生命的基础。血浆湍流还限制了潜在的未来融合能反应器的性能。该研究计划将开发一个新的平台，用于在实验室中产生湍流的等离子体以及测量血浆湍流的新方法。该奖项还支持开发开放式等离子实验室类的巨大努力，其中包括设计，建筑和测试实验室实验，这些实验可以轻松地由其他讲师复制。如果成功的话，这项工作将通过将血浆物理学指导扩展到更广泛的教育机构来增强美国的劳动力。随着流体动力的流体动力湍流的建立，磁化等离子体的湍流是由磁性岛和电流板构建的，这些岛屿和电流板可以在不同的空间范围之间传递磁能。该项目将使用马萨诸塞州理工学院的新的海雀发电机驱动的爆炸性碳线阵列Z-Pinch作为一个磁岛合并平台，以产生磁化的等离子体湍流。这种磁化的等离子体湍流将处于先前未开发的状态：持续，高度碰撞，在驾驶和耗散尺度之间具有离子皮的深度，并在磁性，热和动力学之间近似于能量。 晚期诊断（例如法拉第旋转成像，汤姆森散射和成像折射率）将用于研究从层流到湍流等离子体的过渡。 该诊断将有助于表征离子皮肤深度上方和下方的电谱和间歇性结构的演变，以及强加或自我生成的平均场在相关的湍流结构中的作用。该奖项反映了NSF的法规任务，并被认为是通过基金会的知识优点和广泛的范围来评估的，并被认为是值得通过评估的支持。