This video shows you how particle tracking in a laminar static mixer can be simulated with COMSOL Multiphysics and the Particle Tracing Module. Using the Particle Tracing for Fluid Flow interface and the Laminar Flow interface, you can model the fluid flow and particle trajectories. The static mixer model uses one study to compute the flow field and a second study to compute the particle trajectories due to the drag force. The mixing blades in the geometry cut up the flow field and cause the particles to displace relative to each other, creating a mixing effect. The model uses Poincaré maps and phase portraits to analyze the performance of the mixer.