In most circumstances it is not such a big a problem to select a fan or fan/filter unit for an electrical or electronic enclosure. All you have to do is decide on the minimum airflow rate needed to keep the air temperature below that of the limiting component and pick a fan or fan filter unit of suitable capacity.
For this simple purpose, Axair offers a stock range of fan/filter units with click-fit chevron louvered panels from 105mm to 325mm square. The largest unit will filter air at rates of up to 680m3/h. Amongst the many optional features are IP55 protection, EMC shielding, and a choice of ac or dc electrical supply in standard voltages.
Where filtration is not integrated with the fan there is an enormous range of axial and centrifugal fans to choose from with airflow rates and pressure developments up to and beyond the limits envisaged for enclosure ventilation.
One product worth mentioning is the ‘reverse’ mounted backward-curved motorised impeller. This long technical term describes a type of fan that operates without a scroll housing, overcomes high resistance to air flow, saves space, and saves cost. It is pre-assembled for ease of mounting and electrical connection.
Instead of blowing air directly at the nearest obstacle, the backward-curved impeller first turns it though 90 degrees then projects the air radially. The resulting good air distribution and pressure development makes this fan an ideal product for enclosure ventilation.