Converging heat transfer in completely arbitrary profiles with unconventional thermal concentrator.

Heat transfer manipulation is always an attractive theme in the field of thermal technique and utilization. The proposition of transformation thermodynamics presents great potentials on innovating the conventional thermal techniques with metamaterial. However, only simple designs with uniform profiles have been investigated, as completely arbitrary structures would lead to extreme transformations and singular parameters. These non-negligible problems restrict practical applications of metamaterial concentrators. In this paper, we focus on the heat transfer concentration in "complete" arbitrary profiles through rotatory linear maps. Four schemes, classified into two categories, are demonstrated with homogeneous media configurations. Both distinctive behaviors of internal concentration and external robustness on the thermal fields are significantly observed. Such designs not only efficiently avoid extreme parameters but also provide an alternative way to design metamaterial concentrators under different conditions. The findings may provide new ideas of manipulating heat transfer process, and promoting the novel thermal mate-devices to potential utilization. [ABSTRACT FROM AUTHOR]