VC uniform temperature plate radiator design guide
1. VC radiator is better than heat pipe or metal substrate radiator
Although VC can be considered a flat heat pipe, it still has some core advantages. It has a better temperature equalization effect than metal or heat pipes. Can make the surface temperature more uniform (reduce hot spots). Secondly, the use of VC heat sinks can allow direct contact between the heat source and the device, thereby reducing thermal resistance; while the heat pipe usually needs to be embedded in the substrate.
2. Use VC to equalize temperature instead of transferring heat like a heat pipe Heat pipes are ideal for connecting the heat source to the distal fins, especially for relatively tortuous paths. Even if the path is straight, heat pipes are used instead of VC for remote transfer of heat. This is the key difference between heat pipes and VCs. The focus of heat pipes is to transfer heat.
3. Use VC when the Thermal Budget is tight The maximum ambient temperature of the product minus the maximum temperature of the die is called Thermal Budget. For many outdoor applications, this value is greater than 40°C.
4. The VC area should be at least 10 times the area of the heat source Like heat pipes, the thermal conductivity of VC increases with length. This means that the VC with the same size as the heat source has almost no advantage over the copper substrate. A rule of thumb is that the area of VC should be equal to or greater than ten times the area of the heat source. In the case of large Thermal Budget or large air volume, this may not be a problem. However, in general, the basic bottom surface needs to be much larger than the heat source.
5. Choose VC form according to application requirements Everyone should be familiar with the traditional VC, which is made of two stamped metals (two-piece design). This design can be made into any shape to suit the needs.
6. Other considerations
Size-There is no limit in theory, but VC used for cooling electronic equipment rarely exceeds 300-400 mm in the X and Y directions. Thickness is a function of capillary structure and power dissipation. Sintered metal core is the most common type, and the thickness of VC is between 2.5-4.0mm.
Power density-The ideal application of VC is that the power density of the heat source is greater than 20 W/cm 2, but in reality many devices exceed 300 W/cm 2.
Protection-The most commonly used coating for heat pipes and VC is nickel plating, which has anti-corrosion and aesthetic effects.
Operating temperature-Although VCs can withstand multiple freeze/thaw cycles, their typical operating temperature range is between 1-100 ℃.
Pressure-VC is usually designed to withstand a pressure of 60 psi before deforming. However, it can reach up to 90 psi.
