Modeling of fluids and interfaces via synthesis of integral equations and Mayer-sampling cluster integral calculations

通过综合积分方程和迈耶采样簇积分计算对流体和界面进行建模

• 批准号: 0854340
• 负责人: David Kofke
• 金额: $ 30万
• 依托单位: SUNY at Buffalo
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0854340&HistoricalAwards=false
• 关键词: Modeling; fluids; interfaces; via; synthesis

0854340KofkeIntellectual Merit. This project aims to develop and apply methods for calculating cluster integrals that appear in statistical mechanical theories of fluids. The primary method used is the Mayer sampling approach that was developed and refined in prior work. The present work is focused on the calculation of virial coefficients, and has two general thrusts. First, the project aims to improve methods for calculating these coefficients. Efforts here consider better characterization of the temperature dependence, more efficient grouping of the clusters to minimize the computational effort, and use of approximate integral equation closures to reduce the magnitude of the necessary Mayer sampling integrals and thereby reduce the error in their calculation. The second project goal is to study the performance and improve the application of the virial treatment in characterizing fluid phases. The aim is to better characterize the convergence of the virial series, and determine how it may be applied to approximately locate vapor liquid critical points, particularly as applied to mixtures. The work also looks to develop reformulations or approximants that can improve the range of application of the virial series.Broader Impact. Advances from this research have intrinsic potential for broad impact in chemical thermodynamics. The ability to rapidly move from a molecular model to its macroscopic properties can facilitate the formulation of molecular models that are better able to characterize fluid phases. This in turn can yield truly predictive capabilities in material properties over a useful range of conditions, given only molecular specifications and thermodynamic state. The results of this research would thus produce an enabling technology that can lead to progress in other fields in many unforeseen ways. At a minimum, this research will eliminate the need to ever perform a molecular simulation of a vapor phase or supercritical material, instead permitting a much more efficient and accurate characterization through a molecular based virial treatment. This capability can be useful for diverse applications, such as characterization of gas-phase molecular clustering, or phase equilibria calculations performed in the Gibbs ensemble, or study of solute partitioning in supercritical fluids; notably, all of these capabilities are important to energy and environmental applications.Several special forms of dissemination are performed to ensure that this work is readily adopted by others. Graphically oriented software applications are developed and made available via the web. Different versions of this software are, respectively, designed to: (1) permit the user to generate clusters meeting particular specifications, in a form suitable for use by his or her own computer codes, or simply for presentation pictorially for instruction or contemplation; (2) calculate cluster integrals and virial coefficients for arbitrary potentials using the methods being developed in the project; and (3) identify pure fluid and mixture critical points given values of the virial coefficients.

0854340Kofke智力价值。该项目旨在开发和应用流体统计力学理论中出现的簇积分计算方法。使用的主要方法是在之前的工作中开发和完善的 Mayer 采样方法。目前的工作重点是维里系数的计算，有两个总体主旨。 首先，该项目旨在改进计算这些系数的方法。 这里的努力考虑更好地表征温度依赖性、更有效地对簇进行分组以最小化计算工作量，以及使用近似积分方程闭包来减少必要的 Mayer 采样积分的大小，从而减少其计算中的误差。第二个项目目标是研究维里处理在表征流体相方面的性能并改进其应用。 目的是更好地表征维里级数的收敛性，并确定如何将其应用于近似定位蒸气液体临界点，特别是应用于混合物时。这项工作还寻求开发可以改善维里级数应用范围的重新表述或近似形式。更广泛的影响。这项研究的进展具有对化学热力学产生广泛影响的内在潜力。从分子模型快速转向其宏观特性的能力可以促进分子模型的制定，从而更好地表征流体相。反过来，仅在分子规格和热力学状态的情况下，这可以在有用的条件范围内产生材料特性的真正预测能力。因此，这项研究的结果将产生一种使能技术，能够以许多不可预见的方式推动其他领域的进步。至少，这项研究将消除对气相或超临界材料进行分子模拟的需要，而是允许通过基于分子的维里处理进行更有效和更准确的表征。 此功能可用于多种应用，例如气相分子簇的表征，或在吉布斯系综中进行的相平衡计算，或超临界流体中溶质分配的研究；值得注意的是，所有这些能力对于能源和环境应用都很重要。进行了几种特殊形式的传播，以确保这项工作很容易被其他人采用。面向图形的软件应用程序是通过网络开发和提供的。该软件的不同版本分别设计用于：（1）允许用户以适合他或她自己的计算机代码使用的形式生成满足特定规范的簇，或者仅用于以图形方式呈现以供指导或思考； (2) 使用项目中开发的方法计算任意势的簇积分和维里系数； (3) 在给定维里系数值的情况下确定纯流体和混合物的临界点。