Fig. 1. Diagram of spatial transformation process.

Fig. 2. Transient temperature profiles of three structures at different times: (a) single concentrator, (b) single rotator, (c) co-effect structure, the black arrows represent heat flux. The dimension of the whole simulation domain is 0.8 cm × 0.8 cm, both upper and lower boundaries are thermally isolated, left and right boundaries are respectively fixed at temperature T = 400 K and T = 100 K, leading to an applied temperature gradient of 375 K/cm. The medium of background area outside the function region is set with θ₀ = 0.16 W/(m⋅K) and ρc = 1.358 × 10⁻³ MJ/(m³⋅K) and thermal conductivity of the transformed domain are arranged as theoretical work. The geometric parameters of annuls region are set as R₁ = 0.15 cm, R₂ = 0.23 cm, and R₃ = 0.25 cm.

Fig. 3. (a) Diagram of measured line, (b) temperature distribution on the measured line along y direction of three structures.

Fig. 4. Profiles of components of the transformed local entropy production rate at t = 0.3 s in three structures: (a1) and (a2) single concentrator; (b1) and (b2) single rotator; (c1) and (c2) co-effect structure.

Fig. 5. Variations of different constitutes of anisotropic thermal conductivity in annuls from inner boundary to outer boundary of three structures: (a) κxx′, (b) κxy′(κyx′), (c) κyy′.

Fig. 6. Variations of the transformed total entropy generation S˙g with different variables in three structures, the applied temperature gradient is 375 K/cm and R₃ = 0.25 cm: (a) R₂ = 0.23 cm, θ₀ = π/3, (b) R₁ = 0.09 cm, θ₀ = π/3, (c) R₁ = 0.15 cm, R₂ = 0.23 cm.