momentum exchange of coupled DPM!!

winnie

Hi

I have some questions about the momentum exchange calculations in coupled DPM.

The exchange is calculated via the equation:

F=¡Æ(drag_force+other force)*mass_flow*time_step

Can you tell me if I have four injections each with a definite mass-flow rate, how does the fluent calculate this exchange value when I use following methods:

(1) a steady calculation with only four particles tracked ;

(2) an unsteady calculation with both injection start time and stop time set to zero(that is to say, during the calculation, there are only four particles in the field);

(3) an unsteady calculation with a difference between start time and stop time(that is to say, during each iteration time step, there will be other four paricles injected into the field and the particles in the field are accumulated);

Any help will be appreciated!!

Regards

winnie