HySPH - Mist

Mist is very important for believable mid or large scale simulations. In nature, mist produced when a fluid drop is fragmented into smaller droplets and scattered. This fragmentation process is known as “droplet breakup” and is characterized by the ratio between aerodynamic forces and the droplet’s surface tension. Large water droplets have weaker surface tension forces compared to aerodynamic forces, so they have an increased chance of splitting into smaller droplets. Though we are talking about droplets here, it is important to know that mist cannot be exported as particles. In RealFlow, mist is the graphical representation of a fog-like density field and hence completely different from splashes and foam. You will not find any particle-specific parameters. By default, the density data is stored in “OpenVDB” files, a widely supported open-source file format. Alternatively, you can use the "Field3D" format.

Since mist is a consequence of fragmented splash (and wet) particles, the presence of a grid splash emitter is essential.

Mist clouds from a waterfall.