[Rakeshvb]

Hello experts,
I have a technical query related to the pressure drop measurement in an enclosure. When we use a smaller axial fan (e.g., an exhaust fan) in an enclosure, will it cause an additional pressure drop? See below image from a CFX simulation. Towards the fan entry, there is a sudden drop in pressure. Is this due to a sudden contraction of the flow path? Is this behavior expected if we use a cooling fan on any device?

Initially, I have simulated using MRF/Frozen rotor approach; A similar behavior is observed.

The attached image is a simplified case, where conditions are:

Inlet: Static Pressure 0Pa
Outlet (After the fan): Mass flow rate is specified

[ghorrocks]

The pressure drop as you approach the fan inlet is just Bernoulli's equation - as the fluid speeds up its pressure will reduce.