In this tab, you can control all the settings that drive the look of your sim.
Controls are separated into two sections. At the top, you have a list of sliders and toggles that let you enable and change the strength of the various settings.
Below you have extra settings tabs for each of the settings. Some settings are simple enough that all they need is a strength slider. Some are more advanced and have many additional options.
What algorithm to use when particle velocities are converted to grid velocities and then back to particle velocities. Velocities need to be converted to grids because the way Paradigm and most solvers preserve the incompressibility of a fluid only work on grids.
Simply copies the grid velocity to the particles. This makes the particles velocity very smooth as it completely replaces any uniqueness the particle velocities had before as the velocities were effectively averaged when converted to grids.
Copies back only the differences in the grid velocities before and after project non-divergent. This allows for more particle uniqueness in their velocities. You may sometime see this referred to as “splashiness” in other solvers and tools. There is a blend parameters that allows for some of the pure sampled velocity value to be mixed in as full FLIP does appear very noisy when used at full strength.
You can control the look and motion of the simulation with these settings.
Acceleration acceleration towards a defined direction, typically negative Y.
In the simplest sense you can think of this as an internal friction of velocity values. As fluid moves past each other they start to have their velocity values blurred together. This makes simulations behave more and more sticky or thick as you increase the value. Water might have close to no viscosity, honey a moderately high value, and lava a very high value.
This causes a fluid to want to assume a shape that has the least surface area (a sphere) because all water particles are pulling on each other with equal force. Particles at the surface will thus be pulled towards particles deeper inside the fluid. This causes the fluid to form droplets. You would use this to simulate smaller scale fluids and to achieve things like zero-gravity, dripping, and crown splashes.