Movement of bead in flow

Hi, I would like to (in a first step) model the movement of a bead in flow. This would be very similar to the demo here : https://www.youtube.com/watch?v=iyA5UiBJY0Q

Except that in this case the bead would not be in a fixed position but convected by the flow. Any pointer to how to do that ?

Thank you very much.