Fluid Sim with Geo Nodes

Here is my Blender geometry nodes setup that can simulate fluid as individual particles, both in 2D and 3D. In realtime! With accurate collisions (limited to spheres) and waves simulation.

V1.1 update:

• Removed 'Amount' and 'Spread' and now the volume of the input geometry is used to spawn particles inside.
• You can now also select another object to spawn particles from.
• Added tooltips for all sliders.
• Used repeat-zones to calculate multiple collisions per frame, therefor this update now requires Blender 4.0

Note that it has no 'real' viscosity yet (particles are only repellent and not attractive) and the particles can only collide with spheres, not with meshes.

• Simple fluid particle simulation with geometry nodes in Blender
• Particles collide with each other and other (animated) spheres
• The walls are made of very large spheres... bit of a hack but worked for my purposes
• Parameters for changing 2D/3D, particle count/resolution, speed, viscosity, buoyancy and waves settings
• Material showing the velocity as colors (or height/vertical position of the particles)
• Pretty understandable geometry nodes setup with labelled nodes and nod groups for customization
• Works with Blender 3.6 (uses simulation nodes) and later

You can replace the input mesh to spawn particles in any shape you like. You could easily destroy Suzanne if you so please...

The High Quality checkbox doubles the number of particle collisions per frame. Usually disabling it will give an accurate enough result, and will keep your simulation running smoothly.

Missing: attractive force to simulate accurate viscosity, collisions with meshes, gravity (now the particles 'float' on the surface, see video). Also, the self collision group could be improved by using repeat zones.

Note that I cannot provide in-depth support for this file as I am quite busy at the moment..

Here is a video explaining how to add walls and collider objects.