Hi All,

hope everyone is well.

How does one determine if cooling or ventilation is required from a product? if worst case scenario is assumed from the power consumption in watts can approx temperature of an enclosure be determined?

I know this is vague but just gauging how this is done, looking at my Glaxy S7 Edge i can see some vents on the bottom for the speaker but everything else is sealed (to aid the IP rating), does this not impact on life performance? for every 10Celsius over ambient cuts electronics life in half?

cheers

 

... looking at my Glaxy S7 Edge i can see some vents on the bottom for the speaker but everything else is sealed (to aid the IP rating), does this not impact on life performance?

For an object as small as a phone, with the large surface area to volume shape, passive ventilation would add only a small contribution to heat dissipation. Radiation and convection (to surrounding air) would be relatively much more important.

The general answer to your question is that you have to do a heat balance that considers the heat generation, and the losses due to conduction, radiation and convection. These can all be estimated fairly well with models. The result of the calculations will show a balancing temperature at which the losses of heat match the power input. If that temperature is too high, you have to devise a way to remove more heat. Active ventilation (a fan) is a common solution.