Hydrodynamic and magnetohydrodynamic instabilities in differentially-rotating stars

差异旋转恒星中的流体动力学和磁流体动力学不稳定性

• 批准号: 2443617
• 金额: --
• 依托单位: University of Leeds
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2443617
• 关键词: Hydrodynamic; magnetohydrodynamic; instabilities; differentially; rotating

Observational advances in helio- and astero-seismology have highlighted our poor understanding of the mechanisms of chemical mixing and angular momentum transport in the stably-stratified radiation zones of the Sun and other stars. This project will study various hydrodynamic or magnetohydrodynamic instabilities in stellar and planetary interiors that could contribute to mixing and angular momentum transport. These processes can modify the internal rotations, structures and evolutionary ages of stars, but they are commonly either neglected or modelled in an ad-hoc manner in current stellar models. This project will involve a combination of linear analysis and numerical simulations to understand the properties of one or more of these instabilities, and to determine their nonlinear behaviour. One of the ultimate goals of this project is to understand the nonlinear outcome of these instabilities and another is to provide simple parameterisations of their mixing and angular momentum transport properties that can be incorporated in stellar models.

太阳和天体地震学的观测进展突显了我们对太阳和其他恒星的稳定层状辐射区中的化学混合和角动量传输机制的认识不足。这个项目将研究恒星和行星内部的各种流体动力学或磁流体动力学不稳定性，这些不稳定性可能有助于混合和角动量传输。这些过程可以改变恒星的内部自转、结构和演化年龄，但在当前的恒星模型中，它们通常要么被忽视，要么被临时建模。这个项目将包括线性分析和数值模拟的结合，以了解其中一个或多个不稳定的特性，并确定它们的非线性行为。这个项目的最终目标之一是了解这些不稳定性的非线性结果，另一个是提供它们的混合和角动量输运性质的简单参数，可以纳入恒星模型中。