Novel flow control strategies for heat transfer enhancement in a minimal array of impinging jets

用于在最小冲击射流阵列中增强传热的新型流量控制策略

• 批准号: 1603720
• 负责人: Ahmed Naguib
• 金额: $ 31万
• 依托单位: Michigan State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-08-01 至 2021-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1603720&HistoricalAwards=false
• 关键词: Novel; flow; control; strategies; heat

PI: Naguib, AhmedProposal Number: 1603720The goal of the proposed research is to investigate the flow behavior of arrays of jets used in several engineering applications - most prominent of which is turbine blade cooling in gas turbine engines. In addition, cooling effects that the flow from the jets generates when it impinges on a surface will be studied. The proposal is motivated by the significance of impinging jets for heating, cooling and drying in many industrial processes and engineering devices. A particularly significant application is turbine blade cooling in gas turbine engines, where effective cooling can have a strong favorable impact on engine efficiency, causing substantial reduction in fuel consumption and pollution. The goal of the proposed work is to study the potential for significant augmentation of heat transfer in impinging jet arrays using active flow control strategies. The control strategies, which are conceived based on detailed understanding of the spatio-temporal relationship between the jet's vortical structures and the surface heat flux, will be implemented using plasma actuators mounted around the lips of axisymmetric jets arranged in an inline array. The array size is kept to a minimum of three to enable reproduction of fundamental jet-jet interaction phenomena while avoiding the complexity of large-size arrays. The study will employ time-resolved flow visualization and phase-locked PIV measurements to capture flow-field information simultaneously with measurements of the average convection heat transfer coefficient using temperature-sensitive paint, and spatio-temporal wall heat flux information using thin-film gage arrays. Data will be acquired for a range of parameters including jet-to-impingement-wall spacing, jet-to-jet spacing, Reynolds number, control strategies/parameters, and crossflow presence. This work will result in the education of a graduate student and the involvement of undergraduate students in research, who will also be actively involved in the dissemination of the research to summer high-school students. The graduate and undergraduate researchers will be recruited from underrepresented groups with the aid of existing programs at Michigan State University. New course content will be developed on experimental fluid dynamics that will integrate results from this research.

PI：Naguib, Ahmed 提案编号：1603720 拟议研究的目标是研究多种工程应用中使用的射流阵列的流动行为 - 其中最突出的是燃气涡轮发动机中的涡轮叶片冷却。此外，还将研究喷射流撞击表面时产生的冷却效果。该提案的动机是冲击射流在许多工业过程和工程设备中用于加热、冷却和干燥的重要性。一个特别重要的应用是燃气涡轮发动机中的涡轮叶片冷却，其中有效的冷却可以对发动机效率产生强烈的有利影响，从而大幅减少燃料消耗和污染。拟议工作的目标是研究使用主动流量控制策略显着增强冲击射流阵列传热的潜力。这些控制策略是基于对射流涡流结构和表面热通量之间时空关系的详细理解而构思的，将使用安装在以直列阵列排列的轴对称射流边缘周围的等离子体执行器来实施。阵列尺寸保持在最小三个，以便能够再现基本的射流-射流相互作用现象，同时避免大尺寸阵列的复杂性。该研究将采用时间分辨流可视化和锁相 PIV 测量来捕获流场信息，同时使用温敏涂料测量平均对流传热系数，并使用薄膜测量仪测量时空壁热通量信息数组。将采集一系列参数的数据，包括射流到冲击壁间距、射流到射流间距、雷诺数、控制策略/参数和横流存在。这项工作将导致研究生的教育和本科生参与研究，本科生也将积极参与向暑期高中生传播研究成果。研究生和本科生研究人员将在密歇根州立大学现有项目的帮助下从代表性不足的群体中招募。新的课程内容将基于实验流体动力学开发，并将整合这项研究的结果。