Suggestion please

newbie

Hi, I am trying to model the flow of particles (DPM) in a fluid. In a given zone of the fluid the particles will be under the effect of a force. So that zone must be well defined.

My question is if there is a better way to do that. I mean, should I define the coordinates of the zone in the UDF? or if there is some kind of griding trick or zone definition I could use to know if the particles are in such zone? (as in the example in the UDF manual about rxion that only occurs in the porous section of the grid).

For me the last solution could be better as the solution could be easily generalized to any geometry.

Thanks for any suggestion

Newbie