[hwet]

Good day

I want a udf for the discrete phase to be activated only when the particle passes through a cell with a specific property.

For example, the DEFINE_DPM_BC is activated only when the particle hits a wall. But, here I am trying to activate the UDF while the particle is travelling away from the walls and only when it passes through a cell with a certain property.

To be specific the cells representing a different eulerian phase which is moving constantly as well. So the UDF is called only when the particle enters such a cell.

Is this even possible to achieve? Am i looking at a DEFINE_ON_DEMAND macro? Usually the DPM macros are called at everytime step but this wont be very efficient in my case where the cell occupied by the eulerian phase is only a small fraction of the total number of cells.