The importance of radiation in heat sink design
Often times the role radiation plays in the design of a heat sink is overlooked. There are many references that state a percentage value for the heat dissipated from a heat sink. As with most phenomena in physics and engineering the effect of radiation cannot be generalized with one constant number.
There are several factors that determine the influence of radiation on the performance of a heat sink. Before investigating those factors a brief description of radiation is necessary.
Thermal radiation is electromagnetic waves emitted from all matter that has a temperature above 0 Kelvin (absolute zero). The maximum heat (Watts) that can be emitted from a surface due to radiation is given by:
is the surface area of the radiating surface
is the surface temperature in Kelvin