I‘m looking for a product (final product solid, preferred that it can take a large lateral load) that‘s thermal resistance can be manipulated (electrically). It must be able to go from a very low resistance (prefereably 0) to up to ideally R 5/si (square inch). This is used for a geothermal temperature regulation system. Anything that will point me in the right direction will get best answer, don‘t spam.
The acoustic and thermal properties of graphite are highly anisotropic, since phonons propagate very quickly along the tightly-bound planes, but are slower to travel from one plane to another. Graphite can conduct electricity due to the vast electron delocalization within the carbon layers (a phenomenon called aromaticity). These valence electrons are free to move, so are able to conduct electricity. However, the electricity is only conducted within the plane of the layers. Graphite and graphite powder are valued in industrial applications for its self-lubricating and dry lubricating properties. There is a common belief that graphite's lubricating properties are solely due to the loose interlamellar coupling between sheets in the structure
I'm not sure such a product exists. Certainly homogenous materials don't meet any of these specs. Copper has one of the highest thermal conductivities. You could do something with sheets of copper stacked on top of each other, which are separated by a motor to increase the thermal resistance. You can also do something with a liquid or liquid/gas flow that can be turned off via an electric valve. A liquid that boils from the heat can absorb and transfer a lot of heat. .
