Leveraging Metamaterials and Phase Control in ThermoAcoustic Systems

该研究项目的目标是通过使用超材料和声波控制的创新概念推进热声能源发电领域，从而使国家利益受益。这种系统有可能通过提供传统能源系统的清洁和可持续替代品来彻底改变现代能源生产。热声系统不涉及燃烧，因此减轻了对美国经济中基于化石燃料的能源的环境足迹的主要担忧。热声系统的实现有可能影响广泛的应用，包括空间发电，太阳能收集和废热回收。几乎所有的热声系统都受到两个固有的限制：低功率密度和设计复杂性。该奖项支持基础研究，通过利用动力学和控制工具结合声学超材料独特的滤波能力来解决这两个限制。多学科项目将开发新的工具，以加强学生在动力学、声学和可持续能源生产领域的学习经验，并将通过一系列外联活动扩大代表性不足群体的参与。热声发生器（TAG）是一种设计用于从热源自发产生强大声波的设备，然后将其利用为电力或机械运动。它们有可能接近热力学所施加的熵极限。该项目旨在通过开发一种新型的基于超材料的TAG来达到这一极限，该TAG依赖于压力和速度之间的相位的最佳控制，从而防止在声学谐振器中形成永久驻波。所需的声学条件实现没有额外的散装结构。相反，从热声叠层的小而复杂的孔中出现的不可避免的非线性将用于合成新的TAG腔室，该TAG腔室使得行进的热声波能够传播到谐振器的一端（其中通过电声转换进行能量清除），同时阻止边界反射。这项工作将结合联合收割机工具，从动态系统理论与国家的最先进的实验和实验室规模的调查。这一奖项反映了NSF的法定使命，并已被认为是值得通过评估使用基金会的智力价值和更广泛的影响审查标准的支持。

This objective of this research project is to benefit the national interests by advancing the field of thermoacoustic energy generation using innovative concepts in metamaterials and acoustic wave control. Such systems have the potential to revolutionize modern-era energy generation by providing a clean and sustainable alternative to traditional energy systems. Thermoacoustic systems involve no combustion and therefore mitigate major concerns over the environmental footprint of fossil-fuel-based energy in the U.S. economy. The realization of thermoacoustic systems has the potential to impact a wide range of applications including space power generation, solar energy scavenging and waste heat recovery. Almost all thermoacoustic systems suffer from two inherent limitations: Low power density and design complexity. This award supports fundamental research to address both limitations by leveraging tools from dynamics and controls combined with the unique wave filtering capabilities of acoustic metamaterials. The multi-disciplinary project will develop new tools to enhance the learning experience of students in the fields of dynamics, acoustics and sustainable energy generation, and will broaden participation of underrepresented groups through a range of outreach activities. ThermoAcoustic Generators (TAGs) are devices engineered to spontaneously generate powerful sound waves from a heat source which are then harnessed as electricity or mechanical motion. They have the potential to approach the entropic limit imposed by thermodynamics. This project seeks to reach this limit by developing a novel class of metamaterial-based TAGs which rely on the optimal control of phasing between pressure and velocity which prevents the formation of permanent standing waves in the acoustic resonator. The desirable acoustic conditions are achieved without additional bulk structures. Instead, inevitable nonlinearities emerging from the small and complex pores of the thermoacoustic stack will be used to synthesize a new TAG chamber that enables traveling thermoacoustic waves to propagate to one end of the resonator (where energy scavenging takes place via electro-acoustic transduction) while impeding boundary reflections. This work will combine tools from dynamic systems theory with state-of-the-art experimental and laboratory-scale investigations.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.