Thermal Metamaterials and Heat-Flow-Shaping Structures: Effective Conductivity, Interfaces and Experimental Validation

A process window for the thermal-metamaterial response is only meaningful if it preserves the mechanism that generated the accepted result. The present review identifies that mechanism through the coupled balance that governs heat-flow-shaping structures, then follows how geometry error can create thermal short circuits or bottlenecks and how radiation and convection contaminate apparent conduction in porous/open structures. The recommended evidence combines calibrated full-field temperature mapping, heat-flow measurements, as-built path geometry and constituent conductivity testing. Rather than relying on a broad parameter sweep, the validation strategy uses the controlled test 'rotate anisotropic samples relative to imposed gradient' to expose causality. This supports a technology decision about whether a homogenised tensor is sufficient for design while keeping model and measurement uncertainty visible.

ER-367.