
58 Heat Transfer: Thermal Management of Electronics
Natural convection is the heat transfer mechanism responsible for heating the whole air
inside a room by a heater located at one corner of that room. First, the air near the heater
gets hot. The hot air is lighter than the neighboring colder air. Since in a mixture of
uids the lighter uid moves up, the hot air rises and the neighboring colder air replaces
it and goes through the same process. This process will increase the air temperature in
the entire room. Heat transfer from a human body is partly due to natural convection.
Examples of electronics that are cooled by natural convection