Thermal Transfer and Heat Guides

From en.wikipedia.org/wiki/Heat_pipe, “A heat pipe is a heat-transfer device that employs phase transition to transfer heat between two solid interfaces.

“At the hot interface of a heat pipe, a volatile liquid in contact with a thermally conductive solid surface turns into a vapor by absorbing heat from that surface. The vapor then travels along the heat pipe to the cold interface and condenses back into a liquid, releasing the latent heat. The liquid then returns to the hot interface through either capillary action, centrifugal force, or gravity and the cycle repeats.

“Due to the very high heat transfer coefficients for boiling and condensation, heat pipes are highly effective thermal conductors. The effective thermal conductivity varies with heat pipe length, and can approach 100 kW/(m⋅K) for long heat pipes, in comparison with approximately 0.4 kW/(m⋅K) for copper.”

Robert Murray-Smith. 2015. How To Make A Heat Pipe (or solar heat collector). Video. Retrieved from youtube.com/watch?v=60PctdoRHd0.

Robert Murray-Smith. 2015. Improved Heat Pipe: Over 95% Efficient. Video. Retrieved from youtube.com/watch?v=kfTlPTMt85o.

In these videos, the principles and applications of heat pipes (including their use in solar water heaters) are discussed, and the construction of a simple heat pipe made out of water and copper tubing and end-caps is documented.

Robert Murray-Smith. 2015. Graphene Based Thermal and Solar Fluid. Video. Retrieved from youtube.com/watch?v=ycICsb-lOa8.

From the video's description, “A useful solution of graphene for improving absorption of light and transfer of heat [is presented]. It could well improve the efficiency of solar panels and cooling systems.”