Modeling and Simulation of the Giant Electrocaloric Effect

电热效应是一种物理行为，材料的温度由于施加电场而发生变化。近年来，人们发现一些铁电材料表现出非常大的电热响应，或称“巨”电热效应。提出的研究目标是开发计算建模和仿真工具来研究铁电陶瓷材料的热效应。然后，这些工具将用于研究铁电材料中的热、机械和电场，并预测由这些材料制成的冷却装置的性能和效率。拟议研究的社会效益源于这样一个事实，即世界上几乎所有的冷却和制冷技术都是基于制冷剂的蒸汽压缩循环。基于蒸汽压缩循环的制冷系统通常体积庞大，因为冷却剂膨胀成气态，需要压缩机中的活动部件，并且在某些情况下对环境的影响不太理想。最近在铁电陶瓷中发现的巨大的电热效应可能会导致新的固态冷却技术，这些技术节能、可靠、便携和环保。利用电热效应的薄膜装置可以对制冷、热泵、空调、能量清除和计算机冷却产生重大影响。在本研究计划中开发的计算模拟工具将有助于理解铁电体的基本热电行为，并有助于固态冷却装置的设计。

The electrocaloric effect is a physical behavior where the temperature of a material changes due to the application of an electric field. Recently it has been discovered that some ferroelectric materials exhibit a very large electrocaloric response, or "giant" electrocaloric effect. The goal of the proposed research is to develop computational modeling and simulation tools to study the electrocaloric effect in ferroelectric ceramic materials. These tools will then be used to study the thermal, mechanical and electrical fields in ferroelectric materials, and to predict the performance and efficiency of cooling devices made from these materials.The societal benefits of the proposed research stem from the fact that virtually all of the world's cooling and refrigeration technology is based upon the vapor-compression cycle of a refrigerant. Refrigeration systems based upon the vapor-compression cycle are generally bulky given that the coolant expands into a gaseous state, require moving parts in the compressor, and in some cases have a less than optimal environmental impact. The relatively recent discovery of the giant electrocaloric effect in ferroelectric ceramics may lead to new solid state cooling technologies that are energy efficient, reliable, portable, and environmentally friendly. Thin film devices that utilize the electrocaloric effect could have a significant impact on refrigeration, heat pumps, air conditioning, energy scavenging, and computer cooling. The computational simulation tools developed in the proposed research program will facilitate the understanding of the fundamental thermo-electrical behavior of ferroelectrics and will aid in the design of solid state cooling devices.