Inverse thermal models and techniques

In heat conduction, the analogy between heat flow and electrical intensity is a classic tool for engineers: heat diffusion is a consequence of a temperature gradient, just as the intensity of a current results from an electrical potential difference. While this analogy is a practical tool for calculations, it's much trickier to apply experimentally: it's not as easy to measure heat flow as it is to measure electrical intensity: there's no such thing as a "thermal ammeter" that connects between two faces or two internal points on a wall and simply, directly and instantaneously gives the thermal power flowing through it.

There's an art to building a fluxmeter, a device that is inserted into a medium through which the flow to be measured passes. For such an instrument, the difficulty lies in converting the output signal (often a temperature difference between the two...