Nanoscale Metal Network Enhanced Phase Change Materials

可再生能源，如太阳能、地热能和风能，需要有效和高效的储热系统。潜热储存是一种可以使用某些材料来实现的方法，包括那些被称为相变材料的材料，它们具有在接近恒定温度下储存能量的能力。然而，大多数相变材料具有不可接受的低导热性，因此它们在高功率、瞬态和大规模可再生能源系统中的应用受到极大限制。该奖项支持研究一种制造工艺，以合成并嵌入纳米级金属网络到相变材料中，利用金属网络的高导热性，显着提高基于相变材料的储能系统的热性能。这种新型相变材料将影响可再生能源存储行业以及柔性电子、电子冷却和智能纺织品等多种应用。从这个项目中获得的知识也将有助于其他行业，如医疗，汽车，食品加工和半导体封装。基础研究与教育工作的结合将推动工程教育，并在高中和大学新生中推广这一令人兴奋的科学新领域。本研究的目的是合成并研究一种新型嵌入金属纳米线网络的相变材料的结构、工艺和热性能之间的相互关系。纳米颗粒分散相变材料存在的主要问题是熔融-凝固循环过程中的沉降和颗粒的高界面热阻。重点研究了新型相变材料开发中的基本问题，如纳米线与纳米线之间的焊接、纳米线与侧壁表面的焊接、相变材料流体中磁场与纳米线的相互作用等。将采用建模和理论分析相结合的方法，以及精心设计的实验集来了解网络结构、处理参数（如磁场强度、纳米线负载、磁垫间距和尺寸、焊接温度）与新相变材料的热性能之间的关系。

Renewable energy sources such as solar energy, geothermal energy, and wind energy require effective and efficient thermal storage systems. Latent heat storage is an approach which can be accomplished using certain kinds of materials, including those known as Phase Change Materials, which have the ability to store energy at near constant temperature. However, most Phase Change Materials have unacceptably low thermal conductivities, and therefore their applications for high power, transient, and large-scale renewable energy systems are significantly limited. This award supports the study of a manufacturing process to synthesize and embed a nanoscale metallic network into phase change materials, taking advantage of the high thermal conductivity of the metallic network, to significantly improve thermal performance of Phase Change Material-based energy storage systems. This new type of Phase Change Materials would impact the renewable energy storage industry and diverse applications such as flexible electronics, electronic cooling, and smart textiles. The knowledge acquired from this project will also contribute to other industries such as medical, automobile, food processing and semiconductor packaging. The integration of fundamental research together with the educational efforts will advance engineering education and promote this new and exciting field of science at the high school senior and college freshmen levels.The objective of this research is to synthesize and study interrelationship among structures, processing and thermal properties of a novel phase change material embedded with a soldered metallic nanowire network. The major issues in nanoparticle-dispersed phase change materials include the settlement during melting-solidification cycling, and high interfacial thermal resistance of particles. The research is focused on fundamental issues in exploiting the new phase change material, such as soldering of nanowire-to-nanowire, nanowire-to-sidewall surface, and interactions between magnetic field and nanowires in phase change material fluids. A combined approach involving both modeling and theoretical analysis, and well-designed sets of experiments will be adopted to understand the relationships between network structure, processing parameters such as magnetic field strength, nanowire loading, spacing and size of magnetic pads, soldering temperature, and the resulting thermal properties of the new phase change material.