modeling a flow on a rotating disk
 

I have to model the flow of a Newtonian fluid falling on a rotating disk, initially full of air. However, the fluid instead of expanding on the disc shaped patches :confused:. The drops are formed irregularly on the disc.
I do not understand because this happens.

I am using the VOF model.

Can you tell me what may be the cause, if you faced a similar problem and want to contact me my mail is maurodr.86 @ libero.it

Thanks in advance