Convective thermal cloaks with homogeneous and isotropic parameters and drag-free characteristics for viscous potential flows.

Although convective thermal cloaking has been advanced significantly, the majority of related researches have concentrated on creeping viscous potential flows. Here, we consider convective thermal cloaking works in non-creeping viscous potential flows, and propose a combination of the separation of variables method and the equivalent-medium integral method to analytically deduce the parameters of convective thermal cloaks with isotropic-homogeneous dynamic viscosity and thermal conductivity. Through numerical simulation, we demonstrate the cloaks can hide the object from thermo-hydrodynamic fields. Besides, by comparing the drag force cloaks bear in cloak case and the objects bear in object-existent case, we find convective thermal cloaks can considerably reduce the drag force, which appears drag-free characteristics. Finally, it is our hope that these developed methods can reduce the difficulties of metadevices fabrications, promote the development of drag reduction technology under higher Reynolds number, and shed light on the control of other multi-physics systems.