CAREER:Control of Radiative Thermal Transport Using Nanostructured Materials

1253692 Shen辐射热传输在各种应用中至关重要，例如热绝缘、能量转换、热特征控制和热管理。尽管近场辐射热传递（其中两个表面之间的间距小于由维恩定律给出的热波长）已被证明由于倏逝波的隧穿而超过黑体辐射，但是最大化不同材料之间的近场增强仍然具有挑战性。近场辐射换热的控制将为新的辐射冷却和热能转换技术的发展提供巨大的潜力。在远场中，两个表面之间的差距远大于热波长，在期望频率下的热发射的光谱和方向控制将产生低功率相干红外源，并实现新颖的热管理策略。该项目的目标是使用纳米结构材料（例如，超材料）在近场和远场中。该项目的智力价值在于推进辐射热传输的基础知识。该项目开发的新型计算工具将克服计算复杂三维结构近场辐射的理论障碍，这对于准确预测近场纳米结构材料的热响应至关重要。拟议的超灵敏实验平台，它可以解决小到100皮瓦的热通量，将使近场测量各种纳米结构材料。对于远场辐射控制，该项目将展示两种变革性的科学现象：（一）辐射热通量的高速调制，以及（二）在所需频率下对热发射的光谱和方向控制。 近场和远场辐射热传输的控制将影响能量转换和热管理的广泛应用。本项目中描述的可调超材料将使设计更好的热光伏能量转换系统成为可能。使用超材料对热辐射进行光谱和方向控制将产生低功率红外源，并产生灵活，紧凑和高效的热管理技术，特别是用于冷却航天器。热通量调节器可以允许以高速率打开和关闭热传递，这对于开发先进的热管理策略将是非常有用的。该项目将通过互动教育工具包、课程开发和推广活动，将研究和教育结合起来。将开发两个互动教育套件及其相关的教育计划，以激发学生对能源和纳米科学的兴趣。当地的教育重点将是匹兹堡科学技术学院和奥尔德迪斯高中，以及卡内基梅隆大学的学生。匹兹堡当地的活动将吸引更多的观众，包括年度西门子竞赛和英特尔国际科学与工程博览会。卡内基梅隆大学的课程创新将向研究生和本科生介绍能量转换的基本原理以及辐射热传输的最新研究成果，如近场辐射和超材料。

1253692ShenRadiative thermal transport is of primary importance in various applications such as thermal insulation, energy conversion, thermal signature control and thermal management. Although near-field radiative heat transfer, where the spacing between two surfaces is smaller than the thermal wavelength given by Wien's law, has been demonstrated to exceed blackbody radiation due to the tunneling of evanescent waves, maximizing near-field enhancement between different materials remains challenging. Control of near-field radiative heat transfer will offer significant potential for the development of new radiation cooling and thermal energy conversion technologies. In the far-field, where the gap between two surfaces is much larger than the thermal wavelength, the spectral and directional control of thermal emission at desired frequencies will create low-power coherent infrared sources and enable novel thermal management strategies. The objective of this project is to control radiative thermal transport using nanostructured materials (e.g., metamaterials) in both near- and far-fields. The intellectual merit of this project is in advancing the fundamental knowledge of radiative thermal transport. The novel computational tools developed in this project will overcome the theoretical obstacles in calculating near-field radiation for complex three-dimensional structures, which is critical for accurately predicting the thermal response of nanostructured materials in the near-field. The proposed ultra-sensitive experimental platform, which can resolve a heat flux as small as 100 picowatts, will enable the near-field measurements on a variety of nanostructured materials. For far-field radiation control, this project will demonstrate two transformative scientific phenomena: (i) high-speed modulation of radiative heat fluxes, and (ii) spectral and directional control of thermal emission at desired frequencies. Control of radiative thermal transport in both near- and far-fields will impact a broad range of applications in energy conversion and thermal management. The tunable metamaterials described in this project will make it possible to design better thermophotovoltaic energy conversion systems. The spectral and directional control of thermal emission using metamaterials will create low-power infrared sources and yield flexible, compact and efficient thermal management technologies, especially for cooling spacecrafts. The heat flux modulator can allow the opening and closing of heat transfer at a high rate, which will be extremely useful for developing advanced thermal management strategies. This project will integrate research and education via interactive educational kits, curriculum development, and outreach activities. Two interactive educational kits and their related educational program will be developed to stimulate the students' interests in energy and nanoscience. The local education focuses will be Pittsburgh Science and Technology Academy and Allderdice High School, as well as students at Carnegie Mellon. Broader audiences will be reached at the local events in Pittsburgh including the annual Siemens Competition and the Intel International Science and Engineering Fair. Curriculum innovation at Carnegie Mellon will introduce graduate and undergraduate students to basic principles of energy conversion and the latest research results in radiative thermal transport such as near-field radiation and metamaterials.