FAQs

Whenever a heat dissipation area of more than 5cm is required, a vapor chamber fits the bill. Some vapor chambers can be made to 0.2mm or less, so thickness/space requirements are not a priority.

The vapor chamber is a two-dimensional flat heat pipe that features a large contact area with the heat source and a lower thermal contact resistance, resulting in greater heat conductivity than a heat pipe. The vapor chamber is flat and can be made into curved and complex shapes, unlike heat pipes which can only be straight or curved. The vapor chamber can also be fitted with more heat sink fins than the heat pipe, resulting in a relatively large heat transfer.

For high power 600W and above, such as 1U servers, the space limitation makes it difficult for multiple heat pipes to achieve the heat transfer effect, so the problem of height limitation can be solved by using a high-power large-size heat spreader with a thickness of 4mm.

The vapor chamber, like the heat pipe, is a tool for heat conduction and requires either natural or forced air-cooled convection at the condensing end for the vapor chamber to be effective.

Factors affecting the heat transfer coefficient of a vapor chamber include vacuum, working substance filling, capillary structure, porosity, wetted area, capillary radius, workmanship, etc.

Both heat pipes and vapor chambers are fast heat transfer elements designed using the same two-phase flow (liquid and gas) principle, so they are both used to transfer heat quickly. The difference between the two is that heat pipes transfer heat point to point in one direction, while hot plates transfer heat point to plane. So for larger heat sources with higher wattage, one can choose to use a larger number of heat pipes to transfer the heat, whereas for smaller heat sources with higher wattage where a larger number of heat pipes cannot be used, one can choose to use a hot plate to transfer the heat point to plane from a concentrated heat source.

A vapor chamber is a vacuum chamber with microstructured walls. When heat is transferred from the heat source to the evaporation zone, the working fluid inside the chamber will begin to vaporize in the liquid phase in a low vacuum environment. At this point, the working fluid absorbs heat and expands rapidly, and the working substance in the vapor phase quickly fills the chamber. When the vapor phase working fluid comes into contact with a colder area, condensation occurs. The heat accumulated during evaporation is released through the phenomenon of condensation and the condensed liquid phase working fluid is returned to the evaporative heat source by capillary phenomena in the microstructure. The process is repeated in the chamber and this is how the vapor chamber operates.