Collaborative Research: Continued Support for Development of a Distributed Computing Infrastructure for Computational Thermodynamics in Petrology

该提案为软件开发和分布式计算基础设施的扩展能力寻求资金，以支持岩石学界的计算热力学（CT）需求。这项工作的目的是创建一个在集中计算集群（服务器）上执行的CT函数和方法库。该服务器资源又通过一种与语言无关的低带宽Internet通信协议提供给联网的远程客户机。服务器功能包括检索化学计量相、矿物固体溶液、混合挥发相和多组分硅酸盐液体的热力学性质的方法，以及使用内部一致的热力学数据库执行均匀和非均匀平衡计算的能力。远程客户端（可能是用户编写的）可以像引用本地软件库一样调用服务器计算资源。提供Java小程序供下载，以解决特定的应用（例如，矿物相的热力学性质，固液平衡的计算，熔体包裹体中的包裹后结晶）。还建议将熔融硅酸盐液体中硫和混合挥发物的溶解度模型作为服务器功能，以及熔融硫化物液体的热力学性质模型。此外，服务器代码将被重新构造，以便在多处理器环境中有效地运行。在客户端，我们的目标是对melt小程序进行改进，并提供一些其他专门的工具，包括一个通用的地温计小程序，它允许用户操作矿物固溶体性质的内部一致的热力学数据库，以便配置和利用针对特定共生的矿物地温计。本提案的一个重要目标是构建一个原型应用程序，以演示CT分布式计算环境对计算流体动力学（CFD）代码的开发和执行的效用。将建立一个解决火山管道对流过程的原型CFD客户端。该客户端将依赖于CT服务器基础设施提供的相平衡、焓、密度和物理性质的精确计算。该提案的智力价值在于，它将为全球的研究人员和学生提供在计算热力学中执行复杂计算的能力，并在他们自己的工作中直接利用这些结果，或者间接地从他们在远程计算机系统上开发的应用程序中利用这些结果。CT计算通常难以编码，且测试耗时；可靠的结果通常需要优化的硬件。CT服务器项目为岩石学界提供了最先进的工具，并为其提供了可靠的执行平台。这项提议的更广泛影响是，它将资助一个可能对全球科学界产生重大影响的互联网资源。目前，每天有超过1000名用户登录我们的服务器，其中很大一部分用户来自美国以外，超过一半的用户来自课堂活动。如果该提案得到资助，CT服务器将继续运行，资金带来的资源增强可能会显著提高使用率。此外，研究生和本科生的培训是实现本提案研究目标的一个组成部分。

This proposal seeks funding for software development and expanded capabilities of a distributed computing infrastructure to support computational thermodynamics (CT) needs of the petrological community. The effort is aimed at creation of a library of CT functions and methods that execute on a centralized computing cluster (server). This server resource is in turn made available to networked remote clients via a languageindependent, low-bandwidth Internet communication protocol. Server capabilities include methods to retrieve thermodynamic properties of stoichiometric phases, mineral solid solutions, mixed volatile phases, and multicomponent silicate liquids as well as the ability to perform both homogeneous and heterogeneous equilibrium calculations using an internally consistent thermodynamic database. Remote clients, which may be user written, can call upon server compute resources as if referencing local software libraries. Java applets are provided for download that address specific applications (e.g., thermodynamic properties of mineral phases, calculations of solid-liquid equilibria, postentrapment crystallization in melt inclusions). It is also proposed to incorporate solubility models for sulfur and mixed volatiles in molten silicate liquids as server capabilities as well as models for the thermodynamic properties of molten sulfide liquids. In addition, the server-code will be restructured to run efficiently in a multi-processor environment. On the client-side, the objective is to make improvements in the MELTS applet, and to provide a number of other specialized tools including a generic geothermometer applet that will allow the user to manipulate an internally consistent thermodynamic database of mineral solid solution properties in order to configure and utilize mineral geothermometers tailored to specific parageneses. A significant objective of this proposal is to construct a prototype application that demonstrates the utility of a CT distributed computing environment to the development and execution of computational fluid dynamics (CFD) code. A prototype CFD client will be built that addresses the process of volcanic conduit convection. This client will rely on accurate accounting of phase equilibria, enthalpy, density and physical properties all provided by the CT server infrastructure.Intellectual merit of this proposal is that it will provide a global community of researchers and students with the ability to perform sophisticated calculations in computational thermodynamics and to utilize these results directly in their own work or indirectly from within applications that they develop on remote computer systems. CT calculations are often difficult to code and time-consuming to test; reliable results often require optimized hardware. The CT server project empowers the petrologic community with stateof-the-art tools and offers a reliable platform for their execution.Broader impact of this proposal is that it will fund an Internet resource that could have a significant impact on the global scientific community. There are currently in excess of 1,000 users of MELTS and related CT clients per day logged from our server, with a large percentage of users from outside the US and with over half the usage originating from classroom activity. If this proposal is funded the CT server will remain operational and resource enhancements resulting from funding will likely increase usage significantly. Additionally, both graduate and undergraduate student training is an integral aspect of achieving the research objectives of this proposal.