Dear all I need to do errosion simulationfor tribology application in ansys fluent, as I am not familiar very well, I have some question.

We have a surface which being hited by water and sand, I defined K-epsilon modeling, disceret phase modeling,

Now my question is how can I get angel to the particles? I want to define for example, liquid and particle hit to the surface with the angel of 30 degree, and go out from outlet with this angel but I could not find any thing related.

Any body can help?

And there is any important point that I should consider?