Synthetic simulation of turbulent flow using resolvent analysis

使用解析分析的湍流综合模拟

• 批准号: 2454030
• 金额: --
• 依托单位: University of Southampton
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2454030
• 关键词: Synthetic; simulation; turbulent; flow; using

In turbulent flows, transport processes and average flow quantities of great practical relevance are dominated by coherent structures. In an effort to better understand their role, a sophisticated approach - Resolvent Analysis (RA) - has emerged in recent years. The power of RA is that it yields a set of spatial modes describing the most important flow structures directly from the equations of motion and from knowledge of the mean flow, without requiring expensive scale-resolving simulations or experiments. However, RA only describes the kinematics of fluid motion and lacks the power to explain how structures across different scales interact dynamically with each other.The overarching aim of this project is to develop a methodology that can "close" a RA-based model. The fundamental idea is to determine amplitude coefficients to "weigh" the contribution of different structures such as to balance dynamical behaviour, thus providing a space-time turbulent velocity field that has been generated synthetically, without simulation. From a computational standpoint, this can be achieved by solving an optimisation problem of rather small dimension, owing to the compressive power of RA. The potential of the approach is that it would enable obtaining detailed insight into the dynamics of complex flows more cheaply than with scale-resolving simulation. In turn, this would facilitate and accelerate flow analysis, parameter exploration and engineering design in a variety of applications. The specific objectives of this research are to develop new algorithms and computational tools to suit this paradigm and to demonstrate the method in a variety of three-dimensional fluid systems of practical interest, such as turbulent flows in pipes/channels and separated flows around bluff and streamlined bodies.

在湍流中，运输过程和巨大实践相关性的平均流量由连贯的结构主导。为了更好地理解其角色，近年来出现了一种复杂的方法 - 解决方法分析（RA）。 RA的力量是，它产生了一组空间模式，这些空间模式直接从运动方程和平均流程的知识中直接描述了最重要的流量结构，而无需昂贵的规模分辨率分辨率的模拟或实验。但是，RA仅描述了流体运动的运动学，并且缺乏解释跨尺度的结构如何相互动态相互作用的能力。该项目的总体目的是开发一种可以“关闭”基于RA的模型的方法。基本思想是确定“权衡”不同结构（例如平衡动力学行为）的贡献的振幅系数，从而提供了一种无需模拟而生成的时空湍流速度场。从计算的角度来看，这可以通过解决RA的压缩能力的优化问题来实现。该方法的潜力是，它可以使对复杂流动的动力学的详细见解比使用量表分辨率模拟更便宜。反过来，这将有助于和加速流动分析，参数探索和工程设计在各种应用中。这项研究的具体目的是开发新算法和计算工具以适合这种范式，并在各种三维实际感兴趣的三维流体系统中演示该方法精简的身体。