Selected-Eddy Simulations (SES): a revolutionary approach for turbulence simulations

选定涡模拟 (SES)：一种革命性的湍流模拟方法

• 批准号: 2040114
• 负责人: Diego Donzis
• 金额: $ 30.27万
• 依托单位: Texas A&M Engineering Experiment Station
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-01-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2040114&HistoricalAwards=false
• 关键词: Selected; Eddy; Simulations; SES; revolutionary

Turbulent flows can be extremely complex and often not well understood. This lack of fundamental understanding limits our ability to accurately predict the climate, dispersion of pollutants in the atmosphere and the ocean, and to design optimally efficient engines, transportation vehicles, and energy generation systems. Turbulence has a wide range of scales which makes experimental measurements and computational predictions challenging. Over the past 4 decades, significant progress has been made through direct numerical simulations (DNS) which resolve all relevant turbulent scales to improve turbulence models that are critical in automotive and aircraft design. However, DNS are computationally prohibitive in realistic scenarios. The main objective of this project is to develop a potentially transformative approach to simulate turbulent flows, capturing the detailed physics at a fraction of the cost of DNS while improving the accuracy of unsteady turbulent predictions. The project will seek to involve Hispanic men and women students; the principal investigator actively collaborates with several Hispanic organizations to enhance Hispanic students’ experiences, education, and quality of life on campus. This project aims to develop a revolutionary new approach for accurate turbulence simulations at a fraction of the cost DNS and with significant advantages over other low-order approaches such as Large-Eddy Simulations (LES), where large-scale turbulence is computed and smaller scales are modelled. The new approach, termed Selected-Eddy Simulations (SES), is based on solving a subset of scales across the entire spectrum, unlike LES which is limited to low wavenumbers. Thus, SES uses the true dynamics of the Navier-Stokes equations over a subset of all scales. This has tremendous advantages in reproducing Navier-Stokes dynamics especially in flows where small-scale features are critical such as mixing of weakly diffusive species, dispersion of small particles, shocks, and flames. The selection of modeled scales are control parameters in SES. The SES modeling approach will be compared with DNS and LES results to assess accuracy versus computational cost. The study and modeling of unresolved modes will provide insights into the physics of energy transfer and the dynamics of turbulence in general. Thus, a successful SES concept will result in a more complete understanding of the role of turbulent scales and a more accurate, potentially less expensive, computational tool that can be used to predict and control flows critical for a wide range of engineering applications.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.

动荡的流程可能非常复杂，通常不太了解。缺乏基本理解限制了我们准确预测气候，大气和海洋中污染物的分散以及设计最佳高效发动机，运输车辆和能源生产系统的能力。湍流具有广泛的尺度，可以使实验测量和计算预测挑战。在过去的40年中，通过直接数值模拟（DNS）取得了重大进展，该模拟（DNS）可以解决所有相关的湍流尺度，以改善在汽车和飞机设计中至关重要的湍流模型。但是，在现实情况下，DN在计算上是禁止的。该项目的主要目的是开发一种潜在的变革方法来模拟湍流，以DNS成本的一小部分捕获详细的物理，同时提高了不稳定的湍流预测的准确性。该项目将寻求参与西班牙裔男女学生。首席研究员与几个西班牙裔组织积极合作，以增强西班牙裔学生在校园内的经验，教育和生活质量。该项目旨在开发一种革命性的新方法，以占成本DNS的一小部分准确的湍流模拟，并且比其他低阶方法（例如大型模拟（LES））具有显着优势，在该方法中，计算了大规模的湍流并建模了较小的规模。新方法称为选定的涡流模拟（SES），基于求解整个光谱的一部分尺度，这与限于低波数的LE不同。这在复制Navier-Stokes动态方面具有巨大的优势，尤其是在小规模特征至关重要的流动中，例如混合弱不同物种，小颗粒，冲击和火焰的分散。模型量表的选择是SES中的控制参数。 SES建模方法将与DNS和LES结果进行比较，以评估准确性与计算成本。未解决模式的研究和建模将提供有关能量转移物理和湍流动力学的见解。这是成功的SES概念将使对动荡的量表的作用以及更准确，更便宜的计算工具的作用有更全面的了解，该工具可用于预测和控制对广泛的工程应用程序至关重要的流动。该奖项反映了NSF的法定任务，并通过使用基金会的知识优点和广泛影响来评估NSF的法定任务，并被认为是宝贵的支持。