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aure8142 August 2, 2010 09:45

Need help to dynamic mesh
Hi everybody.
I'm french so sorry for my English.
I'm using Fluent under ansys12.1.
I have to simulate a rotating fan in a vertical cylinder (height=12 meters,diameter=5.5 meters).
My fan have a diameter of 5 meters and have 4 blades.
I would like simulate the rotation of the fan at a constant velocity (1500 rpm) and see how the air in the cylinder moved.
I think that the best solution is to use a dynamic mesh , I have read all the topics speaking about "dynamic mesh under fleunt", but I don't know how fill the udf file.I have tried with an example find on internet but I can't compil it.
So please help me
Bests regards

zdeth August 4, 2010 16:31


I am new to fluent but have also been trying to figure out dynamic meshes. (from what I've gathered) I think you might need a 'moving reference frame' rather than setting up a 'dynamic mesh'?, perhaps search around for that. For the example you found not compiling, I may be able to help. I spent a lot of time troubleshooting UDF compiling errors. If you let me know more about your problems with compiling (error, what you are trying to load, what happens when you do) I can try to help,

I'm not very good at writing french, but can read it fairly well if its easier for you to write in french.

aure8142 August 5, 2010 08:06

I have try to use moving refrence frame , but when I look for example the vectors after the computing, I can see on the wall of the blades the velocity which increase on all the diameter .But the velocity are just on the wall of the blades and there is no velocity in the cylinder.Maybe I have to make interfaces between blades of the fan and cylinder's fluid zone?
For the dynamic mesh, I dont' know if I must have all the cylinder meshed and into thsi fluid zone , mesh the fan ? The fan must be a solid zone or a fluid zone?
Normally, fan must be a solid part and maybe I have just to mesh its faces and not it volume .
I am lost

Thanks very much

KHMKI1 April 29, 2012 19:13

Question about dynamic mesh
i use ansys 14, and tried several times to (compile) a udf TO HELP ME MAKE A DYNAMIC MESH, but different error messages appeared, ( while loading a library). SUCH AS,
Opening library "F:\HEAT TRANSFER PAPER\libudf"...
Error: Error code: 998
Error Object: #f
is the reason in MY ansys package ? Or, in the procedure ?
i ll appreciate a helpful reply..

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