SGER: A novel computational approach to multiphase flow

摘要提案编号：CTS-0639446 主要研究员：S. Balachandar 机构：佛罗里达大学：一种新颖的多相流计算方法 该项目的目标是研究相间界面处的分散多相流的变形、质量、动量和能量传递。 从宏观尺度来看，常用的相关性完全忽略了界面耦合的随机性质。 我们将追求能够准确计算平均矩和其他低阶矩的界面耦合的统计表示。 随机方法将在颗粒湍流通道流的背景下开发。将对在完全发展的湍流通道流中运动的有限尺寸颗粒进行直接数值模拟（DNS）。 一系列大规模模拟将考虑湍流通道流中自由移动粒子分布的完全解析 DNS。这些模拟将深入了解介观机制，例如有限尺寸和有限雷诺数粒子的局部优先积累、团簇形成和分散。模拟还将提供有关颗粒对载相湍流的反向影响的详细统计信息。从这个意义上说，这些模拟可能会详细了解多相壁湍流的三维时间相关结构以及它与相应的单相行为有何不同。 这些模拟构成了计算科学和工程学中的一个重大挑战问题，并将推动颗粒流计算模拟的最新技术发展。

ABSTRACTPROPOSAL NO.: CTS-0639446PRINCIPAL INVESTIGATORS: S. BALACHANDARINSTITUTION: UNIVERSITY OF FLORIDASGER: A novel computational approach to multiphase flow The objective of this project is to study dispersed multiphase flow is at the interface between the phases, in terms of deformation, mass, momentum and energy transfer. Commonly used correlations completely ignore the stochastic nature of the interfacial coupling when viewed at the macroscale. A statistical representation of interfacial coupling that is capable of accurately accounting for the mean and other lower order moments will be pursued. The stochastic approach will be developed in the context of particulate turbulent channel flow. Direct numerical simulations (DNS) of finite-sized particles in motion in a fully developed turbulent channel flow will be performed. A sequence of large scale simulations will consider fully resolved DNS of a distribution of freely moving particles in a turbulent channel flow. The simulations will provide insight into mesoscale mechanisms such as local preferential accumulation, cluster formation and dispersion of particles of finite-size and finite Reynolds number. The simulations will also provide detailed statistical information on the back effect of particles on carrier phase turbulence. In this sense these simulations can potentially yield a detailed look at the three-dimensional time-dependent structure of multiphase wall turbulence and how it differs from corresponding single phase behavior. These simulations constitute a grand challenge problem in computational science and engineering and will advance the state of the art in computational simulations of particulate flows..