THERMAL CLOAK WITH ADAPTIVE HEAT SOURCE DESIGNED BY INVERSE PROBLEM APPROACH
Rendering an object invisible has been a long-standing dream of many researchers over the decades, e.g. electromagnetics, acoustics, elastodynamics, thermodynamics, direct current, particle diffusion, etc. Thermal cloak can guide heat flux around a hidden zone smoothly without disturbing the ambient background thermal field. An object in the cloaked zone is absent. Previously proposed thermal cloak is the metamaterial cloak, which is designed through coordinate transformation method. The metamaterial thermal cloak is a passive device, suffering inapplicability for complex geometries and realization difficulty. The coordinate transformation method results in heterogeneous, inhomogeneous and singular physical properties. In this study, a proactive thermal cloak with adaptive heat source is proposed to manipulate thermal field. A heat source zone and a high thermal conductivity zone are combined to construct the thermal cloak. The high thermal conductivity zone, which is infinite in ideal, is positioned around the cloaked zone to insulate it from outer thermal field. The well-designed heat source is arranged out of the high thermal conductivity zone to recover the background thermal field. The conjugate gradient method with an adjoint equation (CGMAE) is introduced to design heat source distribution of the thermal cloak. It is solved as an inverse problem. CGMAE is numerically implemented through the self-programming code and is applicable for any thermal cloak with complex geometries. The heat source cloak can manipulate thermal field proactively and is widely applicable for complex geometry conditions.