The next release of the Caedium CFD software system will be able to simulate the convection and diffusion of a passive species, also known as a passive scalar. A passive species can represent and track additions such as smoke in airflow and dye in water. It can also provide insights on the dispersion of pollutants carried by a fluid.

Caedium Passive Species CFD SimulationPollutant plume released in air from a chimney

Since it is passive, the species has identical physical properties to the primary simulation substance and does not react with it. A passive species is similar to massless particles (streamlines) except instead of being released at discrete points, the passive species behaves as a continuous field like temperature.

Caedium CFD AnimationPollutant plume released in air from a chimney

To simulate a passive species you would typically:

1. Complete a steady-state flow simulation.
2. Enable the passive species.
3. Specify the release of the passive species at an inlet.
4. Configure unsteady simulation parameters, e.g., time step.
5. Visualize, plot, or monitor the passive species.
6. Run the passive species simulation.