Collaborative Research: Extreme Thermal Transport Events in Supersonic and Hypersonic Shock Wave-Turbulence Interactions

合作研究：超音速和高超音速冲击波-湍流相互作用中的极端热传输事件

• 批准号: 2041622
• 负责人: Danesh Tafti
• 金额: $ 19.99万
• 依托单位: Virginia Polytechnic Institute and State University
• 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: 2021-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2041622&HistoricalAwards=false
• 关键词: Collaborative; Research; Extreme; Thermal; Transport

High-speed flows near or exceeding the speed of sound causes intense aerodynamic heating, which requires sophisticated thermal protection systems. The high temperatures combined with extreme flow events, such as shock waves and turbulence, reduce the life of propulsion devices, such as gas turbine engines, high performance aircraft aero-engines, scramjets, rockets, lift-off and reentry vehicles, among others. The project will address complex thermal transport processes during the interactions of shock wave and turbulence with the goal of enabling safer and more reliable aero-propulsion engines. Fundamental understanding will be promoted, along with training, teaching, and learning by means of parallel education/outreach components, such as incorporation of findings in graduate education, and presentations in symposia and conferences. Women, minority students, and undergraduate students will also participate, as well as both teachers and students from local high schools. This project seeks to improve the understanding of thermal turbulence transport by considering: (a) effects of shock wave mode, angle, orientation, and strength, and the sources and modes of shock wave unsteadiness which alter thermal transport and surface heat transfer, (b) the means whereby shock wave unsteadiness alters and propagates into subsonic boundary layer regions to affect near-wall thermal transport mechanisms and surface heat transfer, (c) effects of the strength and relative size of shock wave induced separation on thermal transport, (d) effects of shock wave compression heating, viscous friction heating, and conversion of kinetic energy to internal energy on thermal transport, and (e) resulting alterations to turbulence and scalar fluxes, second order turbulent quantities, and coherence and time lag distributions. Unsteady motions of different types of shock waves and unsteady, spatially-varying surface heat transfer and thermal transport will be considered through a coordinated experimental-computational study. A newly developed supersonic wind tunnel system will be employed, along with large eddy simulations, to provide detailed flow and thermal field characteristics. Crucial causal relationships will be clarified through understanding of: (i) associated thermal transport characteristics, (ii) spatially-dependent and frequency-dependent coherence and time lag between events at different flow conditions, (iii) highly-resolved experimental visualizations of unsteady flow features from which quantitative flow information will be determined, and (iv) spatio-temporal flow and thermal field-data from numerical predictions.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.

接近或超过声速的高速流动会导致强烈的气动加热，这需要复杂的热保护系统。高温与冲击波和湍流等极端流动事件相结合，会缩短燃气涡轮发动机、高性能飞机航空发动机、超燃冲压发动机、火箭、升空和再入飞行器等推进装置的寿命。该项目将解决冲击波和湍流相互作用期间的复杂热传输过程，目标是实现更安全、更可靠的航空推进发动机。将通过并行教育/推广部分（例如将研究结果纳入研究生教育以及在研讨会和会议中进行演示）来促进基本理解以及培训、教学和学习。女性、少数民族学生和本科生以及当地高中的教师和学生也将参加。该项目旨在通过考虑以下因素来增进对热湍流传输的理解：(a) 冲击波模式、角度、方向和强度的影响，以及改变热传输和表面传热的冲击波不稳定的来源和模式，(b) ) 冲击波不稳定性改变并传播到亚音速边界层区域以影响近壁热传输机制和表面传热的方式， (c) 冲击波引起的分离的强度和相对尺寸对热传输的影响， (d)冲击波压缩效应加热、粘性摩擦加热以及热传输中动能向内能的转换，以及 (e) 由此产生的湍流和标量通量、二阶湍流量以及相干性和时滞分布的变化。将通过协调的实验计算研究来考虑不同类型冲击波的不稳定运动以及不稳定的、空间变化的表面传热和热传输。将采用新开发的超音速风洞系统以及大涡流模拟，以提供详细的流动和热场特征。通过理解以下内容，可以阐明关键的因果关系：(i) 相关的热传输特性，(ii) 不同流动条件下事件之间的空间相关性和频率相关性相干性和时间滞后，(iii) 非定常流动的高分辨率实验可视化确定定量流量信息的特征，以及 (iv) 来自数值预测的时空流量和热场数据。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准。