Investigation of the effects of turbulent flow on energy and mass transfer close to solid surfaces

研究湍流对固体表面附近能量和质量传递的影响

• 批准号: 1803014
• 负责人: Dimitrios Papavassiliou
• 金额: $ 32.56万
• 依托单位: University of Oklahoma Norman Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1803014&HistoricalAwards=false
• 关键词: Investigation; effects; turbulent; flow; energy

Turbulence is the most common type of fluid flow in both the industry and the environment, while it is still one of the unsolved problems in physics. Its ability to mix and disperse energy or mass (like chemicals or particles) plays a key role in every day applications, like flows in oil and gas pipelines, in industrial reactors, in mixing, in heating or cooling, as well as in the atmosphere and in oceans. The goal of this project is to understand the effects of flow features that are commonly observed in turbulent flow on the transport of energy and mass using advanced computational techniques. The findings of this research could lead to efficient energy management, efficient design of industrial equipment where heat and mass transfer take place, and better prediction and control of pollutant dispersion. The database generated through this project will become available to the scientific community, and simulation data generated through this project will be used to develop animations of turbulent dispersion that can be used in K-12 science demonstrations.Central concerns for the development of a comprehensive turbulent transport theory have been the prediction of the spatial variation of turbulent viscosity, the effect of molecular dispersion on turbulent transport, and the effect of coherent velocity structures on the transport properties. The main hypothesis here is that the reason for the failure in predicting scalar transfer from momentum transfer is that only some of the velocity structures participate in turbulent transfer close to a wall, and the range of scales that participate in the transfer depends on molecular dispersion effects. Main questions to be answered are what is the role the very large scales of motion (known as VLSM) in turbulent transport, and how the interplay between molecular diffusion and convection affects mixing or separation of particles in anisotropic turbulence. The proposed approach is to use computations with Lagrangian methods for analysis, which afford the study of a range of fluids that span several orders of Prandtl number in magnitude (e.g., liquid metals, gases, refrigerants, and electrochemical fluids) making it possible to handle cases where conventional methods are often not feasible with the current supercomputers. Expected results could lead to the development of a comprehensive model for the prediction and control of turbulent transport.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.

湍流是工业和环境中最常见的流体流动类型，但它仍然是物理学中尚未解决的问题之一。它混合和分散能量或质量(如化学品或颗粒)的能力在日常应用中发挥着关键作用，如石油和天然气管道中的流动、工业反应堆中的流动、混合、加热或冷却中以及大气和海洋中的流动。该项目的目标是利用先进的计算技术了解湍流中常见的流动特征对能量和质量传输的影响。这项研究的结果可能导致高效的能源管理，高效的工业设备的设计发生热量和质量传递，并更好地预测和控制污染物扩散。通过这个项目产生的数据库将可供科学界使用，通过这个项目产生的模拟数据将用于开发可用于K-12科学演示的湍流弥散动画。发展综合湍流传输理论的中心问题是预测湍流粘度的空间变化，分子弥散对湍流传输的影响，以及相干速度结构对传输特性的影响。这里的主要假设是，从动量传递预测标量传递失败的原因是，只有部分速度结构参与了靠近壁面的湍流传递，参与传递的尺度范围取决于分子的弥散效应。需要回答的主要问题是超大规模运动(VLSM)在湍流传输中所起的作用，以及分子扩散和对流之间的相互作用如何影响各向异性湍流中颗粒的混合或分离。建议的方法是使用拉格朗日方法进行分析的计算，该方法提供了一系列跨越几个数量级的普朗特数的流体(例如，液体金属、气体、制冷剂和电化学液)的研究，使得有可能处理传统方法在当前的超级计算机上通常不可行的情况。这一奖项反映了NSF的法定使命，通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Using helicity to investigate scalar transport in wall turbulence

• DOI: 10.1103/physrevfluids.5.062601
• 发表时间: 2020-06-23
• 期刊: PHYSICAL REVIEW FLUIDS
• 影响因子: 2.7
• 作者: Nguyen, Q.;Papavassiliou, D., V
• 通讯作者: Papavassiliou, D., V

Coupled Flow and Heat or Mass Transfer

耦合流动和传热或传质

• DOI: 10.3390/fluids5020066
• 发表时间: 2020
• 期刊: Fluids
• 影响因子: 1.9
• 作者: Papavassiliou, Dimitrios V.;Razavi, Sepideh;Nguyen, Quoc
• 通讯作者: Nguyen, Quoc