Topology optimization methods for thermal metamaterials: A review

Thermal metamaterials are artificially designed structures with exceptional thermal properties that are not present in natural materials, which have enormous potential applications in aerospace, energy, electronics, and other fields. In recent years, a wide range of thermal metamaterials have been designed by topology optimization, but have not been schematically summarized yet. In this review, we focus on the topology optimization methods for thermal metamaterials, which are summarized into three categories: heat-flux driven, temperaturefield driven, and thermal-property driven methods. The optimization models and results of each type of method are elaborated, and their individual characteristics for the design of thermal metamaterials are analyzed. At the end of this review, the development trends of topology optimization methods for thermal metamaterials are prospected in terms of methods for thermal metamaterials considering fabrication constraints, three-dimensional thermal metamaterials with complex shapes, thermal metamaterials under multiple physical fields, thermal metamaterials designed by data-driven method, intelligent thermal metamaterials, thermal convective metamaterials, and thermal metamaterials with some novel functionalities.