Fan Configurations
The three essential fan configurations are ducted fan, forcing fan, and exhausting fan.
Ducted Fan
The fan has both inlet and outlet ducts.

The dynamic pressure is non-zero at both the inlet and outlet.
In this configuration, the fan static pressure is:
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Forcing Fan
The fan upstream is a plenum and the downstream is a duct.

The dynamic pressure is zero at the upstream, but non-zero at the downstream.
In this configuration, the fan static pressure is:
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Exhausting Fan
The fan upstream is a duct and the downstream is a plenum.

The dynamic pressure is non-zero at the upstream, but zero at the downstream.
In this configuration, the fan static pressure is:
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