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Natural Convection
Heat Transfer
Many electronic systems dissipate a relatively small amount of heat and may not
require forced air or liquid ow for cooling. On the other hand, forced air or liquid
ows are generated by fans or pumps that are noisy and have shorter life compared
to most electronic devices. Therefore, it is better to avoid forced convection cooling
in systems that are designed for low maintenance, long life, or low acoustic noise.
Examples of these systems are televisions, video cassette recorders (VCRs), compact
disk (CD) and digital video disk (DVD) players, personal modems and routers and
rewalls, cell phones, hand