I am new to CFD modelling. I tried to simulate the flow of the rotating disk with an inlet flow and an outlet pressure (please refer to the sectioned view of the model below). However, the outlet flow rate is different from the inlet flow rate. I just wonder is that related to my setup.

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General Setting:

Analysis: Internal , exclude cavities without flow condition

Gravity: Y component (-9.81 m/s^2)

Rotation: local region

Flow: Air

Boundary condition:

local rotating region- 219.94 rad/s

Real Wall - Stator

Inlet volume flow- 0.033 m^3/s , uniform, absolute

Environment pressure outlet

The diameter of inlet is 40 mm and outlet is 50 mm.

Results: