Reply To: Number of escaped and trapped particles at each time step

[Rob]

You'd need to run the report every time step. A safer route may be the DPM.out files (DPM Summary) which can be set to report parcels hitting/passing a surface. 

Note, you're tracking parcels. Assuming you've not been setting multiple injections or size distribution or "scale by area" on the surface injection the number of parcels added will be directly proportional to the mass injected.