权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Development of a roughened inner sphere for the three-meter model of the Earth's core

为地核三米模型开发粗糙的内球体

基本信息

批准号：
1909055
负责人：
Daniel Lathrop
金额：
$ 49.34万
依托单位：
University of Maryland, College Park
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2019
资助国家：
美国
起止时间：
2019-08-01 至 2023-01-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1909055&HistoricalAwards=false
关键词：
Development roughened inner sphere three

项目摘要

Our planet's magnetic field directly affects near-Earth radiation during solar storms. This makes it important to understand the process that generates the magnetic field, and also to develop our capacity to predict its changes. This Division of Earth Science Instrumentation and Facilities Program award supports a project which aims to better understand the origin and changes of the Earth's magnetic field. Since these ongoing changes are a result of processes deep in the planet's outer core, it is difficult to do direct studies. The investigators have developed an NSF funded laboratory model of the Earth's outer core: the three-meter liquid sodium experiment. This project will involve a major design modification to the sodium experiment that is needed in order to better mimic the Earth's core, produce model magnetic fields, and enhance our ability to predict magnetic field changes. The project also serves to encourage public appreciation and understanding of geomagnetism through TV and web based documentaries, as well as videos posted on the research group's YouTube channel (www.youtube.com/user/n3umh); to open efforts and activities to non-scientists through frequent tours of the laboratory to a broad range of audiences; and to educate a new generation of scholars in geophysics experiments, including undergraduate mentoring and graduate student training.The Earth's main magnetic field is central to making our planet a habitable home. During solar maximum, solar storms produce deadly charged particle radiation. The geodynamo magnetic field, along with the Earth's atmosphere, serves to shield us from the worst of these. Nonetheless, solar storms can affect radio communications, the power grid, and spacecraft operations. Thus, we are motivated to understand the origins of the Earth's magnetic field, explore its dynamics, and potentially forecast its behavior. While we know the field changes dramatically over time, including through erratic reversals, there is no reliable predictive science for the weather occurring in the core and no full understanding of the Earth's dynamo generation. An NSF-funded three-meter (3-m) laboratory model of the Earth's core produces induced magnetic fields from rotating turbulence, modeling the dynamics of the Earth's core, and can be used for testing dynamo magnetic field forecasting. One second of experiments mimic approximately 5,000 years of core turbulence (based on the relative magnetic dipole diffusion time scales), allowing observations of detailed magnetic field evolution not possible for the Earth. While previous experiments have yielded important results in hydrodynamics and magnetohydrodynamics since operations began in 2008, the 3-m experiment now requires significant design modifications to increase magnetic field gain. This will be critical for continued studies, including those that directly address questions related to dynamo generation and sustenance. This project will undertake a major modification of the 3-m liquid sodium system that will allow attempting dynamo magnetic field action, and open the parameter space of the system to expand the potential of magnetohydrodynamics experiments. The project also makes direct contributions to the public appreciation and understanding of geomagnetism through TV and web based documentaries and frequent facility tours.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.

在太阳风暴期间，地球磁场直接影响近地辐射。这使得了解产生磁场的过程以及发展我们预测其变化的能力变得非常重要。地球科学仪器和设施计划奖的这个部门支持一个旨在更好地了解地球磁场的起源和变化的项目。由于这些持续的变化是地球外核深处过程的结果，因此很难进行直接研究。研究人员开发了一个由美国国家科学基金会资助的地球外核实验室模型：三米液态钠实验。该项目将涉及对钠实验的重大设计修改，以便更好地模拟地核，产生模型磁场，并提高我们预测磁场变化的能力。该项目还通过电视和网络纪录片以及研究小组YouTube频道上的视频鼓励公众欣赏和理解地磁（www.youtube.com/user/n3umh）;通过经常让广大受众图尔斯参观实验室，向非科学家开放各项工作和活动;并在物理学实验方面教育新一代学者，包括本科生指导和研究生培训。地球的主磁场是使我们的星球成为可居住家园的核心。在太阳活动高峰期，太阳风暴产生致命的带电粒子辐射。地球发电机磁场，沿着地球的大气层，保护我们免受最坏的影响。尽管如此，太阳风暴会影响无线电通信、电网和航天器的运行。因此，我们有动力了解地球磁场的起源，探索其动力学，并可能预测其行为。虽然我们知道磁场会随着时间的推移发生巨大变化，包括通过不稳定的逆转，但对于核心发生的天气没有可靠的预测科学，也没有对地球发电机发电的充分了解。美国国家科学基金会资助的一个3米（3米）的地核实验室模型从旋转湍流中产生感应磁场，模拟地核的动力学，并可用于测试发电机磁场预测。一秒钟的实验模拟了大约5,000年的核心湍流（基于相对磁偶极子扩散时间尺度），允许对地球不可能的详细磁场演化进行观测。虽然自2008年开始运行以来，以前的实验在流体力学和磁流体力学方面取得了重要成果，但3米实验现在需要进行重大的设计修改以增加磁场增益。这对继续进行研究至关重要，包括那些直接处理发电和维持问题的研究。该项目将对3米液体钠系统进行重大修改，允许尝试发电机磁场作用，并开放系统的参数空间，以扩大磁流体力学实验的潜力。该项目还通过电视和基于网络的纪录片以及频繁的设施图尔斯之旅，为公众对地磁的欣赏和理解做出了直接贡献。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。