This shelf tool sets up a falling smoke effect resembling dry ice fog. The preset uses a negative Scale Temperature value on the Source Volume node to create cold smoke that will fall instead of rise.
The preset uses a high diffusion rate to make the smoke settle quickly and create the appropriate "drizzling" look.
On the Pyro Solver node, the dissipation range is remapped to start below zero, to correctly evaporate the fog over time.
Use the Disturbance and Turbulence controls on the pyro solver to add detail or change motion. You can also change the Noise and scale settings on the Fluid Source surface node to change the emission of the fog.
If the object has velocity attributes, the Fluid Source SOP will convert them into a velocity field in the simulation.
To add velocity attributes to the object, add a Trail SOP and on the Trail node set Result type to "Compute velocity".
Use the disturbance and turbulence controls on the Pyro Solver’s Shape tab to add detail or change motion.
Use the noise and scale settings on the object’s Fluid Source SOP to change the emission.