MRF Solver fan simulation - problem
Good morning to every one,
I am OpenFOAM user, I am working on axial flow fan. To check the OF result, I am trying to simulate the case in Fluent (This is my first case in Fluent for ever).
I am using MRF - steady state solver in Fluent,
First I tried a passage of a fan (see fig-1 pdf), I got good torque and fluxes but I didnt check the pressure raise. I got good agreement with experimental torque (79 N-m).
I thought the simulation is right, now I am not sure about it.
Secondly, I tried 2 blade with quarter of the cylinder (see fig-2 pdf), I ran the case with same setup, but the torque is strange I got twice of the passage case (168 N-m).
expected torque is 70-80 N-m
I am totally confused, please help guys
Fluent case setup is as follows:
i) Mesh --> check --ok
ii) General --> type - Pressure Based, absolute, and time--> Steady
iii) Material --> air (I didn’t change the properties)
iv) Cell Zone Conditions --> I have 3 zones namely IV - Inlet Volume, FV - Fan Volume and OV - Outlet Volume. here I have selected the Fan Volume --> Frame motion, rotation axis origin - (0 0 0),
rotation axis direction (0 0 1),
rotational velocity (78.54 rad/s)
All periodic I have given Rotational (It was Translational)
wall motion -->Moving wall
motion --> Relative to adjacent Cell Zone and Rotational
speed --> 0 rad/s
rotation Axis Origin --> (0 0 0)
Rotation axis Direction (0 0 1)
Is the settings are correct? if not what should I change?
please give me some hit, what is going wrong.
Thanks for your time and help,
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