Doubts with group injection (DPM)
 

Hi, I'm simulating the airflow in a room and I have to put some particles and follow their trajectories.
I first chose the surface injection but I need a small number of particles (15-20) and I can't change the mesh and how it is now, it have 204 faces/particles.
So I want to use the group injection changing only Y position, I set all parameters and started calculate, but I thought the number of particles would be constant and it keeps increasing. In firts interaction there was 15 but in the next it increase to 5280.
I guess I had set any parameter in a wrong way but I can't find what parameter and I'm only learning to work with the program.

Hope someone can help me, thanks

Luana