Thermacore’s Matt Connors has written up a nice primer on Vapor Chamber technology that’s well worth a read over at Design World Magazine. Among the points he notes:
- Surface area alone is not enough with highly concentrated heat sources such as high-power electronic components. As the electronic components get smaller and the heat sinks base area increases, a large thermal heat spreading penalty is typically found in the base of the heat sink [ATS: meaning? you can only make a heat sink so big before it doesn’t work efficiently with concentrated heat sources]
- To stay within the existing heat sink form factor and to reduce the thermal resistance of the larger base, the heat sink’s standard metallic base needs to be replaced with a conducting material. A vapor chamber can be used as the medium to spread heat in the base more efficiently.
- Vapor chambers are essentially flat or planar heat pipes that use the principles of evaporation and condensation to produce a very high conductivity thermal plane. Vapor chambers are basically evacuated vessels with an internal wick and a working fluid. The wick helps transport the working fluid back to the evaporator surface without using moving parts. Once the fluid evaporates, it travels to the cooler section of the chamber, condenses in the wick, and the cycle continues.
Matt’s got some other choice words as well and his article is a great primer on this topic for our readers.
As Matt notes, vapor chambers are really flat heat pipes.ATS has some resources that can provide you some breadth of information to go with Thermacore’s primer, here’s three ATS Technical White Papers, all for free: