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: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=614645
• 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的，因此对湍流效应的现实模拟至关重要。基于雷诺（Reynolds）的Navier-Stokes（RANS）方法已成为计算湍流，尤其是在Hydroulic和空气动力学方面的主力军。但是，已经发现RANS模型对于具有较大分离的复杂流以及不稳定效应的情况下不足以准确。计算机功率的增加以及更准确，更有效的数值方法的发展导致了大型涡流（LES）方法的发展。发现LES优于RANS，但太昂贵了，无法在实际规模的工程问题中部署。一种更实惠的方法结合了兰斯和莱斯的不同优势。一个人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，流量是使用较便宜的Rans模型计算的。这已被称为混合Rans-LES方法，这是现代CFD实践的一种吸引人的方法。该研究计划的重点是基于混​​合LES-RAN方法的高性能流量求解器的开发以及现代数值方法的投资，以允许高精度和计算性能。更具体地说，我们将研究过度网格和高阶离散方法，以实现湍流所需的高精度。这些应用旨在解决水力学和空气动力学工程中遇到的复杂流动问题，例如溢洪道上的自由表面流或大坝的penstocks，以及围绕飞机结构的兼容流动。