Subashni Ravichandran
Ansys Employee

Hello Mahesh Kannan S

I have gone through your model and following are the observations I made:

  1. I see that in your previous comment you have mentioned the radius as 20mm whereas in the model you shared the diameter was set to 20mm. Changing the diameter to 40mm and deleting the rotating boundary condition ( 0rpm condition) I got the pressure drop close to 180 Pa at max fidelity (64Gb graphics card). This value is much more comparable to the 167Pa obtained from ANSYS Fluent.
    (refer image below)

  2. The Reynold's number for the problem (without rotation) seems to be in the Laminar range. Could you please confirm if the mass flow rate was intentionally set to 0.14kg/s as it seems very low? As k-omega is a turbulence model, it may be advisable to use a laminar model in Fluent to evaluate the results. 
  3. I would also like to clarify that the Rotating wall condition imparts the specified rotational velocity to the wall elements and does not simulate the effect of a fan/rotor.