Reduced Models for Compressible Turbulence in the High-Lundquist-Number Solar Wind

摘要：ATM 00- 001317提案标题：高伦德奎斯特数太阳风中可压缩湍流的简化模型主要研究者：Amitava Bhattacharjee，爱荷华州大学研究人员将研究太阳风中湍流能谱的各向异性和空间不均匀性，并将太阳风等离子体明确地处理为可压缩流体。主要的努力是使用一套减少的磁流体动力学（MHD）量身定制的等离子体制度相关的太阳风来描述相互的，同时相互作用的三个和四个传播波。在过去的几年里，研究人员已经发展出所谓的四场方程组，它在描述中等（~ 1）β的等离子体湍流方面显示出很大的希望。这些方程的数值解进行了比较，并发现在良好的协议，从可压缩MHD模拟的结果。拟议的工作建立在最近的成功基础上。此外，霍尔-磁流体模拟将用于检查发生在较短波长的波-波相互作用过程。最终，四场近似将被扩展到包括这个较短尺度的物理，并在公式中加入广义欧姆定律。

ABSTRACT: ATM 00-001317Proposal Title: Reduced Models for Compressible Turbulence in the High Lundquist Number Solar WindPrincipal Investigator: Amitava Bhattacharjee, University of Iowa The investigators will study the anisotropy and spatial inhomogeneity of the energy spectrum of turbulence in the solar wind, with explicit treatment of the solar wind plasma as a compressible fluid. The main effort is to use a reduced set of magnetohydrodynamic (MHD) tailored to the plasma regimes relevant to the solar winds to describe mutual, simultaneous interactions of three and four propagating waves. Over the past few years the investigators have developed the so-called four-field system of equations that has shown much promise in describing turbulence in plasmas at modest (~ 1) beta. Numerical solutions of these equations have been compared, and found to be in good agreement, with results from compressible MHD simulations. The proposed work builds on this recent success. In addition, Hall-MHD simulations will be used to examine wave-wave interaction processes occurring at shorter wavelengths. Eventually, the four-field approximation will be extended to include this shorter scale physics with the addition of a generalized Ohm's law in the formulation.