A thermal cloak with thermoelectric devices to manipulate a temperature field within a wide range of conductivity ratios.

A technology of active thermal cloaks that use thermoelectric (TE) devices to manipulate heat flow is devised, and its powerful adaptive function is studied quantitatively. Determining the distribution of adaptive heat sources is a critical mission in the design of active thermal cloaks. This can be accomplished by directly solving the heat conduction equation for the device being studied. The input electric current of the TE components can then be determined individually according to the heat source distribution. On this basis, the performance of our designed cloak system is tested by finite element analysis. Simulation results show that even if the thermal conductivity ratio m (of object-to-background) and/or the temperature gradient g of the background temperature field change over a very wide range, TE components can pump the heat flow accurately from one side of the cloak to the other side by adjusting the input current, so that the background temperature field can be restored to its original state to good approximation. Design of an active thermal cloak is no longer limited by material properties and can be adjusted freely according to the thermal environment. The feasibility of active thermal cloaks is demonstrated theoretically by this work. [ABSTRACT FROM AUTHOR]