Physics-based Scale Enrichment for Eddy-Resolving Turbulence Simulations

计算模型广泛用于设计和分析，以支持航空航天、能源和运输部门的新技术。许多这些应用需要精确预测湍流流体流动，通常具有复杂的几何形状。例如，改进航空航天飞行器的气动设计需要预测和管理飞行器表面湍流的阻力。涡流解析湍流模拟是基础科学研究的重要工具，但由于其高昂的成本，在工程应用中才刚刚开始使用。该项目将开发一种基于物理的建模方法，以经济有效的方式显著改善湍流模拟。新方法将为非定常载荷、疲劳、表面振动和声辐射的经济预测提供巨大的潜力。所提出的方法是基于结合涡流解析湍流模拟，如大涡流模拟，尽管带宽有限，与一个有效的，基于物理的尺度富集方案应用于每个计算单元。该富集方案在局部产生细尺度涡流的物理一致性实现，该实现动态响应已分解的更大尺度，并使物理量的统计预测具有更大的带宽，从而能够预测以前无法访问的量。提出了一种新的计算建模策略，该策略具有潜在的应用前景，可用于风能和涉及结构振动和疲劳的航空航天设计/优化等多个领域。除此之外，所提出的方法还可以应用于更广泛的领域，如动态气象学、海洋和大气科学。正在开发的工具和软件将是开源的，并有望在计算科学社区的不同团体之间发起合作和使用。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Computational models are widely used in design and analysis to support new technologies in aerospace, energy and transportation sectors. Many of these applications require accurate prediction of turbulent fluid flows often with complex geometries. For example, improved aerodynamic designs for aerospace vehicles require prediction and management of the drag force of turbulent flow on the vehicle surfaces. Eddy-resolving turbulence simulations, which are an important tool for fundamental scientific research, are only beginning to be used in engineering applications largely due to their very high cost. This project will develop a physics-based modeling approach to significantly improve turbulence simulations in a cost-effective manner. The new method should provide significant potential for cost-effective predictions of unsteady loads, fatigue, surface vibrations, and acoustic radiation.The proposed approach is based on combining eddy-resolving turbulence simulation, such as large-eddy simulation, albeit of limited bandwidth, with an efficient, physics-based scale-enrichment scheme applied at each of the computational cells. The enrichment scheme generates a physically consistent realization of the finer-scale eddies locally which dynamically respond to the resolved larger scales and enable statistical predictions of physical quantities with a substantially larger bandwidth, thus enabling predictions of quantities not accessible previously. A novel computational modeling strategy is proposed with potential applications to diverse fields such as wind energy, and aerospace design/optimization involving structural vibration and fatigue. Beyond these, the proposed approach may have applications in broader fields such as dynamic meteorology and ocean and atmospheric sciences. The tools and software being developed will be open source and is expected to initiate collaborations and use across diverse groups from the computational science community.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.