An Integrated Science Environment for Astrophysical Simulations

天体物理模拟代码以及天体物理数据变得越来越复杂：模拟现在能够探测恒星、星系、黑洞和许多其他不同现象的形成。 然而，随着模拟变得越来越大，并且控制这些模拟的物理模型变得越来越复杂，开发模拟代码和分析从这些模拟输出的数据的固有困难也随之增加。 许多不同的，往往是相互竞争的，团体利用独立的模拟平台，这阻碍了实质性的合作，由于技术不兼容。 为了减轻这种碎片化，这项研究涉及创建一个综合科学环境，用于天体物理计算和可视化。 这个综合科学环境的设计同样适用于新用户以及在诸如NSF资助的Blue沃茨等平台上的千万亿次模拟。 本研究所产生的综合科学环境构建了三个主要组成部分：仿真平台接口，初始条件生成器，分析和可视化引擎。 仿真平台接口将各个仿真平台的内部数据结构和单元处理抽象为物理相关的量，提供了一个兼容层，使微物理求解器（如化学，辐射冷却和流体力学）能够应用于多个平台。 初始条件生成器为天体物理模拟创建起始点，从而实现直观的初始条件生成以及直接的跨代码比较和结果验证。 最后，分析引擎产生高质量的定量结果和可视化，包括天文馆质量的可视化工具。 集成科学环境是完全MPI并行化的，主要用Python编写，具有API，用于在模拟过程中进行原位或并发分析和可视化，可扩展到数十万个处理器。

Astrophysical simulation codes, as well as astrophysical data, have grown increasingly complex: simulations are now able to probe the formation of stars, galaxies, black holes and many other disparate phenomena. However, as simulations become larger, and the physical models governing those simulations become more complex, the inherent difficulties in developing simulation codes and analyzing the data output from these simulations grow commensurately. Many different, often competing, groups utilize independent simulation platforms, which prevents substantial collaboration as a result of technical incompatibilities. To mitigate this fragmentation, this research involves the creation of an Integrated Science Environment for both astrophysical computation and visualization. This Integrated Science Environment is designed to work equally well for new users as well as for petascale simulations on platforms such as the NSF-funded Blue Waters. The Integrated Science Environment produced by this research is constructed out of three primary components: a simulation platform interface, an initial conditions generator, and an analysis and visualization engine. The simulation platform interface abstracts the internal data structures and unit-handling of individual simulation platforms into physically-relevant quantities, providing a compatibility layer enabling microphysical solvers (such as chemistry, radiative cooling, and hydrodynamics) to be applied to multiple platforms unmodified. The initial conditions generator creates the starting points for astrophysical simulations, enabling both intuitive initial conditions generation and straightforward cross-code comparison and validation of results. Finally, the analysis engine produces high-quality quantitative results and visualizations, including planetarium-quality visualization tools. The Integrated Science Environment is fully MPI-parallelized and is written primarily in Python with APIs for in situ or concurrent analysis and visualization to be conducted during the course of a simulation, scaling up to hundreds of thousands of processors.