CAREER: A Novel and Fast Open-Source Code for Global Simulation of Stratified Convection and Magnetohydrodynamics of the Sun

职业生涯：用于太阳分层对流和磁流体动力学全局模拟的新颖且快速的开源代码

• 批准号: 1554005
• 负责人: Chunlei Liang
• 金额: $ 49.72万
• 依托单位: George Washington University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-05-15 至 2019-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1554005&HistoricalAwards=false
• 关键词: CAREER; Novel; Fast; Open; Source

Non-technical: The goal of this project is to create a unique capability for predicting density-stratified magnetohydrodynamics of the Sun. This research is expected to lay a foundation for developing methods for predicting extreme space weather, e.g. the event of a "super solar flare" followed by an extreme geomagnetic storm. Scientific results of this research can help resolve several contradictory predictions from previous studies of the solar convection zone. The Principal Investigator (PI) will develop and disseminate a powerful open-source software package to the space weather and solar physics communities. The success of predicting severe space weather events has significant societal and economic impacts. PI will design high-order accurate computational algorithms suitable for exascale simulations that can perform a billion billion calculations per second. This software will run on massively parallel distributed-memory computers to predict coupled global and local dynamics of the sun. PI will reach out to K-12 students and demonstrate that science of the sun and high-performance computing are exciting and important to society. Furthermore, PI will leverage outreach efforts with the High Altitude Observatory of the National Center for Atmospheric Research and other research centers. This project, thus, serves the national interest as stated by NSF's mission: to promote the progress of science and to advance the national welfare.Technical: The goal of this research program is to develop a novel, fully compressible model and an open-source community code for global simulations of the solar convection zone that includes the top near surface shear layer of the Sun. Current leading global simulations use an elastic approximation whose computational domains extend from the base of the solar convection zone and must stop at about 0.96 solar radius, stopping short of the top near surface shear layer where Mach number could reach unity. This research program will create a powerful open-source community code CHORUS++ to simulate magnetohydrodynamics of the solar convection zone. CHORUS stands for Compressible High-ORder Unstructured-grid Spectral difference code which has been co-developed by the PI for hydrodynamics of the solar convection zone. CHORUS++ will be equipped with variable mesh resolution capability to focus on targeted regions of interests. A fast local time-stepping algorithm will be designed and equipped for CHORUS++ for long-period time integration on massively parallel computers. These technical accomplishments can accelerate the original CHORUS code by a factor over 100. The PI will conduct a series of global simulations of magnetohydrodynamics of the solar convection zone with unprecedented resolutions for predicting the differential rotation, meridional circulation, giant cells, and super-granulation of the sun.

非技术性：该项目的目标是创建一种独特的能力，以预测太阳的密度分离的磁流失动力学。预计这项研究将为预测极端空间天气的方法奠定基础，例如“超级太阳耀斑”的事件随后发生了极端的地磁风暴。这项研究的科学结果可以帮助解决先前关于太阳对流区的研究的几个矛盾预测。首席研究员（PI）将开发并将强大的开源软件包开发到太空天气和太阳能物理社区。预测严重的太空天气事件的成功带来了重大的社会和经济影响。 PI将设计适用于可以执行每秒计算的Exascale模拟的高阶精确计算算法。该软件将在大规模并行分布式内存计算机上运行，​​以预测太阳的全球和局部动力学。 PI将与K-12学生接触，并证明太阳科学和高性能计算对社会来说是令人兴奋且重要的。 此外，PI将利用国家大气研究中心和其他研究中心的高海拔观测站来利用外展工作。 因此，该项目符合NSF的使命所指出的国家利益：促进科学的进步并促进国家福利。技术：该研究计划的目的是开发一种新颖的，完全可压缩的模型，并为包括太阳能对流区域的全球开放式社区守则，其中包括太阳的顶层阳光层面的顶层剪切层。当前领先的全局模拟使用弹性近似，其计算域从太阳对流区的底部延伸，并且必须停在0.96太阳半径上，停止距离马赫数可以达到统一的顶部近表面剪切层。该研究计划将创建一个强大的开源社区代码合唱++，以模拟太阳对流区的磁性水力动力学。 合唱代表可压缩的高阶非结构网格频谱差异代码，该代码已由PI共同开发用于太阳对流区的流体动力学。 合唱++将配备可变的网格分辨率能力，以专注于目标区域。将为合唱++设计和配备快速的本地时间步变算法，以在大规模平行的计算机上进行长期周期时间集成。这些技术成就可以使原始合唱码以100多个因素加速。PI将对太阳能对流区的磁性水动力学进行一系列全球模拟，并以前所未有的分辨率来预测差异旋转，子午线循环，巨细胞和太阳的超级生产。