Autonomously Tuning Multilayer Thermal Cloak with Variable Thermal Conductivity Based on Thermal Triggered Dual Phase-Transition Metamaterial  

作　　者：娄琦 夏明岗 Qi Lou;Ming-Gang Xia(Department of Applied Physics,School of Physics,Xi’an Jiaotong University,Xi’an 710049,China;MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter,School of Physics,Xi’an Jiaotong University,Xi’an 710049,China;Shaanxi Province Key Laboratory of Quantum Information and Optoelectronic Quantum Devices,School of Physics,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]Department of Applied Physics,School of Physics,Xi’an Jiaotong University,Xi’an 710049,China [2]MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter,School of Physics,Xi’an Jiaotong University,Xi’an 710049,China [3]Shaanxi Province Key Laboratory of Quantum Information and Optoelectronic Quantum Devices,School of Physics,Xi’an Jiaotong University,Xi’an 710049,China

出　　处：《Chinese Physics Letters》2023年第9期54-60,共7页中国物理快报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Grant No. 11774278);the Fundamental Research Funds for Central Universities (Grant No. 2012jdgz04)。

摘　　要：Thermal cloaks offer the potential to conceal internal objects from detection or to prevent thermal shock by controlling external heat flow. However, most conventional natural materials lack the desired flexibility and versatility required for on-demand thermal manipulation. We propose a solution in the form of homogeneous multilayer thermodynamic cloaks. Through an ingenious design, these cloaks achieve exceptional and extreme parameters, enabling the distribution of multiple materials in space. We first investigate the effects of important design parameters on the thermal shielding effectiveness of conventional thermal cloaks. Subsequently, we introduce an autonomous tuning function for the thermodynamic cloak, accomplished by leveraging two phase transition materials as thermal conductive layers. Remarkably, this tuning function does not require any energy input. Finite element analysis results demonstrate a significant reduction in the temperature gradient inside the thermal cloak compared to the surrounding background. This reduction indicates the cloak’s remarkable ability to manipulate the spatial thermal field. Furthermore, the utilization of materials undergoing phase transition leads to an increase in thermal conductivity, enabling the cloak to achieve the opposite variation of the temperature field between the object region and the background. This means that, while the temperature gradient within the cloak decreases, the temperature gradient in the background increases. This work addresses a compelling and crucial challenge in the realm of thermal metamaterials, i.e., autonomous tuning of the thermal field without energy input. Such an achievement is currently unattainable with existing natural materials. This study establishes the groundwork for the application of thermal metamaterials in thermodynamic cloaks, with potential extensions into thermal energy harvesting, thermal camouflage, and thermoelectric conversion devices.By harnessing phonons, our findings provide an unprecedented and practical

关 键 词：THERMODYNAMIC autonomous TRANSITION 

分 类 号：TK124[动力工程及工程热物理—工程热物理]