Studies of Magnetohydrodynamic Turbulence and Turbulence in the Corona and Interplanetary Medium

磁流体动力湍流以及日冕和行星际介质中的湍流研究

• 批准号: 0105254
• 负责人: William Matthaeus
• 金额: $ 50.52万
• 依托单位: University of Delaware
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-15 至 2006-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0105254&HistoricalAwards=false
• 关键词: Studies; Magnetohydrodynamic; Turbulence; Corona; Interplanetary

The investigators will perform theoretical investigations of incompressible and nearly incompressible magnetohydrodynamic turbulence and anisotropic linear cascades in the corona and interplanetary medium. Complex nonlinear dynamical behavior, or turbulence, is observed in space plasmas over a wide range of scales that may be described by a magnetohydrodynamic (MHD) model. Many phenomena in the extended solar corona, including the solar wind, in the magnetosphere, and in the interstellar medium may involve turbulence. Turbulence is likely to have importance in coronal heating, the acceleration of solar wind, and the acceleration and diffusion of energetic particles. An integrated approach will be adopted using MHD and fluid simulation techniques, transport theory, analytic theory of turbulence and particle diffusion, and related analysis and interpretation of spacecraft observations. Work in basic MHD theory will include development and refinement of phenomenologies for MHD relaxation and decay processes, further characterization of the nature of MHD spectral anisotropy, and information theory-based attempts to advance a description of coherent structures in MHD turbulence. Advances in phenomenologies and transport models will be used to further develop scattering and transport theories of cosmic rays. Long-term goals are self-consistent models of coronal heating and the acceleration and evolution of the solar wind.

研究人员将对电晕和星际媒介中的不可压缩和几乎不可压缩的磁流失动力湍流和各向异性线性级联反应进行理论研究。 复杂的非线性动力学行为或湍流在广泛的尺度上观察到可以通过磁性水力动力学（MHD）模型描述的范围。 磁层和星际介质中的延长太阳电晕中的许多现象，包括太阳风，可能涉及湍流。 湍流可能在冠状加热，太阳风的加速度以及能量颗粒的加速度和扩散中具有重要意义。 将使用MHD和流体模拟技术，转运理论，湍流和颗粒扩散的分析理论以及航天器观测的相关分析和解释来采用综合方法。 基本MHD理论的工作将包括用于MHD松弛和衰减过程的现象学的发展和完善，对MHD光谱各向异性的性质的进一步表征以及基于信息理论的尝试，以推动对MHD湍流中相干结构的描述的尝试。 现象学和运输模型的进步将用于进一步发展宇宙射线的散射和运输理论。 长期目标是冠状加热的自洽模型以及太阳风的加速和演变。