Core dynamics experiments in the three meter geodynamo device

三米地球发电机装置中的岩心动力学实验

• 批准号: 1114303
• 负责人: Daniel Lathrop
• 金额: $ 49.82万
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1114303&HistoricalAwards=false
• 关键词: Core; dynamics; experiments; three; meter

The Earth's magnetic field is dynamic and has been weakening for the last 160 years. The main field is generated in the Earth's core by the interaction of the rotating, turbulent liquid metal outer core and electrical currents induced by that motion. This project seeks to resolve how the rotation of the planet and turbulence affect the generation of magnetic fields in the Earth's core. At the heart of the project is the University of Maryland's three meter-diameter model of the Earth's core. That model uses 20 tons of rotating liquid metal and vessel to mimic the interaction of magnetic fields, turbulence and rotation in a scale model of the Earth's core. A magnetic sensor array is used to measure the dynamics of magnetic fields induced by the sodium flow. With this array the magnetic Gauss coefficients (spherical harmonic amplitudes) can be determined in order to understand the magnetic and hydrodynamic modes and their dynamics, study of the role of turbulent fluctuations in momentum transport and magnetic field generation, and resolve wave motions and their contribution to geophysical dynamical processes. These magnetic measurements are complimented by diagnostics rotating with the experiment, including torque sensors, ultrasound velocimetry, dynamic pressure probes, and dynamic wall velocity probes. This project includes the initial sodium operations for the three meter system, now that the device and preliminary water experiments are complete.The project science, including the initial operation of a world unique device, is undertaken by a team of young researchers at the University of Maryland. The mentoring and career development experiences of the young scientists involved are an extremely important part of the project. Additionally, high-school science class field trips will be hosted to encourage the next generation of Science, Technology, Engineering, and Mathematics students from diverse backgrounds, while exposing them to an international science project. Finally, the measurements from the magnetic probe array allow the rendering of the magnetic fields into movies in order to convey our observations to the public.

地球的磁场是动态的，在过去的160年里一直在减弱。主磁场是由旋转的、湍流的液态金属外核和由该运动引起的电流的相互作用在地核中产生的。该项目旨在解决行星的旋转和湍流如何影响地球核心磁场的产生。 该项目的核心是马里兰州大学的三米直径的地核模型。该模型使用20吨旋转的液态金属和容器来模拟地球核心比例模型中磁场，湍流和旋转的相互作用。 磁传感器阵列用于测量由钠流引起的磁场的动态。 利用该阵列，可以确定磁高斯系数（球谐振幅），以了解磁和流体动力学模式及其动力学，研究湍流波动在动量传输和磁场产生中的作用，并解决波动及其对地球物理动力学过程的贡献。这些磁测量是由诊断旋转与实验，包括扭矩传感器，超声测速仪，动态压力探头和动态壁速度探头补充。该项目包括三米系统的初始钠操作，现在该设备和初步的水实验已经完成。该项目的科学，包括一个世界上独一无二的设备的初始操作，是由马里兰州大学的一个年轻的研究人员团队承担的。 参与的青年科学家的指导和职业发展经验是该项目极其重要的一部分。 此外，高中科学类实地考察将主办，以鼓励来自不同背景的科学，技术，工程和数学学生的下一代，同时让他们接触到一个国际科学项目。 最后，来自磁探针阵列的测量结果允许将磁场渲染成电影，以便向公众传达我们的观察结果。