Gravitationally Driven Instabilities that Influence Stellar Evolution

影响恒星演化的引力驱动的不稳定性

• 批准号: 0708551
• 负责人: Joel Tohline
• 金额: $ 37.08万
• 依托单位: Louisiana State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-08-01 至 2011-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0708551&HistoricalAwards=false
• 关键词: Gravitationally; Driven; Instabilities; Influence; Stellar; Gravitationally; Driven; Instabilities; Influence; Stellar

AST-0708551TohlineRotating stars are susceptible to a variety of global, gravitationally driven instabilities, especially during the earliest and latest phases of their evolution. Stars in binary systems may encounter an even larger number of instabilities through their mutual gravitational interaction. Once activated, any one of these instabilities can be amplified enough to drive a substantial alteration in the star's global structure, altering its evolution and perhaps emitting measurable gravitational radiation. In fact, the ability to detect gravitational radiation will depend on the accurate prediction of the expected spectrum. This project will extend existing work on gravitationally driven instabilities in rotating stars, using fully three-dimensional, nonlinear hydrodynamical techniques to determine the conditions for certain key instabilities, and to study the astrophysically important implications of the nonlinear development of instabilities.The required computational algorithms and hardware tools also have significant research applications in atmospheric sciences, coastal studies, health sciences, and engineering. Professor Tohline and his group regularly exchange ideas and computational techniques with applied mathematicians, computer scientists, and numerous colleagues who employ computational fluid dynamics in their research to model hurricane storm surges, fluid flow in the human eye, cooling flows in advanced gas turbine systems, coastal erosion, and reacting flows in petrochemical stirring tanks. Most of these areas of research directly influence Louisiana's environmental and economic wellbeing. The research team will also continue their K-12 and general public outreach projects, especially those associated with a local observatory, and with a secondary school where substantial efforts are being made to strengthen the early training of young women in science and mathematics.

AST-0708551 tohlinerotation恒星容易受到各种全球，重力驱动的不稳定性的影响，尤其是在其进化的最早和最新阶段。 二进制系统中的恒星通过它们的相互重力相互作用可能会遇到更多的不稳定性。 一旦激活，这些不稳定性中的任何一个都可以被扩增，以驱动恒星的全球结构的实质性改变，改变其演变，并可能发出可测量的重力辐射。 实际上，检测引力辐射的能力将取决于预期光谱的准确预测。 该项目将使用完全三维的非线性流体动力学技术来扩展现有的重力驱动的不稳定性，以确定某些关键不稳定性的条件，并研究不稳定性非线性发展的天体物理重要含义。所需的计算算法和硬件工具在大气研究中还具有重要的研究算法和硬件研究应用程序。 Tohline教授及其小组定期与应用数学家，计算机科学家以及众多同事交换思想和计算技术，他们在研究中采用计算流体动力学来模拟飓风风暴的潮流，人眼中的流体流动，高级燃气涡轮涡轮系统中的冷却流，沿海侵蚀和沿海腐蚀和反应油的反应流中的烟丝搅拌。 这些研究领域中的大多数直接影响路易斯安那州的环境和经济福祉。 研究团队还将继续其K-12和一般公共外展项目，尤其是与当地观测员相关的项目，并在中学中做出了重大努力，以加强对科学和数学的年轻女性的早期培训。