Can Anyone help me to write a momentum source udf ?
 

I have a fan in the room, i want to simulate this problem but i think in need to define source terms. So i want to write an udf, i am looking for udf manual and examples but i am in a hurry so i need your help. I do not know anything about udf or programming actually so, for example

http://aerojet.engr.ucdavis.edu/flue...df/node232.htm

Can i write udf like this ? Can this solve my problem ? Lets say i can write but how ?

Thanks,