Consolidated Grant in Solar and Planetary Studies: Department of Applied Mathematics, University of Leeds

太阳和行星研究综合资助：利兹大学应用数学系

• 批准号: ST/N000765/1
• 负责人: David Hughes
• 金额: $ 130.57万
• 依托单位: University of Leeds
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2016
• 资助国家: 英国
• 起止时间: 2016 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FN000765%2F1
• 关键词: Consolidated; Grant; Solar; Planetary; Studies; Consolidated; Grant; Solar; Planetary; Studies

Many astrophysical phenomena involve the complex interaction between magnetic fields, rotation and turbulent fluid flows. We intend to undertake a systematic and integrated programme of research to investigate this interaction in a variety of contexts in solar system and planetary sciences. We shall utilise a combination of analytical and numerical techniques (including the application of cutting edge numerical algorithms optimised for use on massively parallel machines) to gain an understanding of such phenomena. Our unifying philosophy is to investigate and explain the underlying fundamental physical interactions in these astrophysical fluids whilst also providing a theoretical underpinning to the latest high-resolution observations. We propose to investigate the following specific problems:(1) The most exciting recent observational discovery in solar physics is the identification of the "solar tachocline", a thin region of strong velocity shear, deep in the Sun, sandwiched between the convective and radiative zones. This was entirely unexpected theoretically. We shall investigate the nature of the shear-dominated turbulent flow in the tachocline to investigate how quantities such as temperature, magnetic field and angular momentum are transported, and hence to understand why the tachocline does indeed exist.(2) On the Sun, magnetic field is observed to exist over a range of spatial and temporal scales, from the large and long-lived to the small and short-lived. Furthermore, the convection at the solar surface also has a range of scales, from supergranules (which are about 20,000 km across) down to granules (about 1000 km). We shall study the interaction between the convection and the magnetic fields to explain these observed ranges in scale.(3) The large-scale magnetic field erupts through the solar surface to cause sunspots in the photosphere and to trigger sometimes violent magnetic activity in the solar atmosphere. The velocity shear in the tachocline winds up the weak poloidal magnetic field into a strong toroidal field, which then escapes, to rise and eventually to appear at the surface. We have developed a new set of equations designed specifically to describe the magnetic field in the tachocline. We shall use these to explain the scale and morphology of the escaping magnetic field, and will then relate our findings to observations of emerging solar magnetic fields.(4) Most planets have magnetic fields, which vary widely in their strength and spatial form. By considering planet-specific computational models,we shall investigate the nature of the dynamo mechanism responsible for generating magnetic field in the gas giants, Jupiter and Saturn, and in the ice giants, Uranus and Neptune. Our results will be related to those of the JUNO mission to Jupiter.

许多天体物理现象涉及磁场，旋转和湍流流量之间的复杂相互作用。我们打算采用系统和集成的研究计划，以在太阳系和行星科学的各种情况下研究这种相互作用。我们将利用分析和数值技术的组合（包括优化用于在大规模平行机上使用的尖端数值算法的应用）来了解这种现象。我们统一的哲学是调查和解释这些天体物理流体中潜在的基本物理相互作用，同时还为最新的高分辨率观察提供了理论的基础。我们建议研究以下特定问题：（1）太阳能物理学中最令人兴奋的观察性发现是鉴定“太阳能tachocline”，这是一个较薄的速度剪切薄的薄区域，在阳光下深处，夹在对流和辐射区域之间。从理论上讲，这是完全出乎意料的。我们将研究速秒剪切主导的湍流的性质，以研究如何运输温度，磁场和角动量等数量，从而理解为什么速粒确实确实存在。此外，太阳表面的对流也具有一系列尺度，从超级颗粒（约20,000 km）到颗粒（约1000公里）。我们将研究对流和磁场之间的相互作用，以在规模上解释这些观察到的范围。（3）大规模的磁场通过太阳能表面爆发，以引起光球中的黑子，并在太阳大气中触发剧烈的磁性活动。速度线中的速度剪切将弱的磁场磁场变成一个强的环形磁场，然后逃脱，升高并最终出现在表面上。我们已经开发了一组新的方程式，专门描述了速度线中的磁场。我们将使用这些来解释逃逸磁场的规模和形态，然后将我们的发现与新兴太阳能磁场的观察相关联。（4）大多数行星具有磁场，其强度和空间形式差异很大。通过考虑特定于行星的计算模型，我们将研究负责在气体巨头，木星和土星以及冰巨头，天王星和海王星中产生磁场的发电机机制的性质。我们的结果将与Juno任务木星的任务有关。