High performance computing methodologies for solving complex turbulent flows

解决复杂湍流的高性能计算方法

• 批准号: RGPIN-2016-03812
• 负责人: Soulaïmani, Azzeddine
• 金额: $ 1.89万
• 依托单位: École de technologie supérieure
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=708428
• 关键词: performance; computing; methodologies; solving; complex

Computational fluid dynamics (CFD) methods are commonly used as tools for solving industrial and environmental engineering problems. As most of these problems are turbulent, the realistic simulation of the turbulence effect is essential. The Reynolds-Averaged Navier-Stokes (RANS)-based approach has become the workhorse for calculating turbulent flows, especially in hydraulics and aerodynamics. However, RANS models have been found to be not sufficiently accurate for complex flows with large separations and where unsteady effects are of interest. The increase in computer power and the development of more accurate and efficient numerical methods have led to the development of large eddy simulation (LES) methodology. LES has been found superior to RANS, but is too expensive to be deployed in real-scale engineering problems. A more affordable approach combines RANS and LES' different strengths; one can use LES only where needed because the flow is too complex, while in other parts of the domain, such as near walls, the flow is computed with the less expensive RANS model. This has become known as the hybrid RANS-LES approach, which is an appealing methodology for modern CFD practice. This research program is focused on the development of a high performance flow solver based on a hybrid LES-RANS approach and on the investigation of modern numerical methods to allow high accuracy and computational performance. More specifically, we will investigate overset-grid and higher-order discretizations methods to achieve the high accuracy required by turbulent flows. The applications are geared towards solving the complex flow problems encountered in hydraulics and in aerodynamics engineering, such as free surface flows over the spillways or the penstocks of dams, and compressible flows around aircraft structures.

计算流体动力学 (CFD) 方法通常用作解决工业和环境工程问题的工具。由于这些问题大多数都是湍流问题，因此对湍流效应的真实模拟至关重要。基于雷诺平均纳维斯托克斯 (RANS) 的方法已成为计算湍流的主力，特别是在水力学和空气动力学领域。然而，人们发现 RANS 模型对于具有大分离度和不稳定效应的复杂流动不够准确。计算机能力的提高和更准确、更高效的数值方法的发展导致了大涡模拟（LES）方法的发展。人们发现 LES 优于 RANS，但部署在实际规模的工程问题中成本太高。一种更实惠的方法结合了 RANS 和 LES 的不同优势；人们只能在需要的地方使用 LES，因为流太复杂，而在域的其他部分，例如靠近墙壁，流是使用较便宜的 RANS 模型计算的。这被称为混合 RANS-LES 方法，对于现代 CFD 实践而言，这是一种颇具吸引力的方法。该研究项目的重点是开发基于混合 LES-RANS 方法的高性能流求解器，并研究现代数值方法以实现高精度和计算性能。更具体地说，我们将研究重叠网格和高阶离散化方法，以实现湍流所需的高精度。这些应用程序旨在解决液压和空气动力学工程中遇到的复杂流动问题，例如溢洪道或水坝压力管上的自由表面流动，以及飞机结构周围的可压缩流动。