Blender: 2D Pyro Solver - Geometry Nodes

Current Version: 2.0

This is a fully functioning 2D pyro solver (smoke simulator) created entirely using Geometry Nodes in Blender. This solver is fully equipped with advanced advection schemes (BFECC, MacCormack, Trace RK4) as well as supports inputs for density, temperature, pressure, color, initial velocity, object velocity and collisions. Unfortunately at the moment, geometry nodes are not super fast at calculating large simulation loops such as this one, so although it is technically possible to convert this 2D solver into a 3D solver (it has already been tested), the simulation times are incredibly slow and unstable. I will continue to improve both this 2D pyro solver and the 3D pyro solver. Over time I will update the 2D pyro solver here, and will upload the 3D solver as a seperate item once it is ready.

Version 2.0 Updates:

• BFECC Advection (as well as options to choose Upwind advection or Semi-Lagrangian advection)
• Improved Advection Trace Modes - Single Step, Trace Midpoint, Trace RK3, RK4, and CFL Adaptive Trace
• Multi-step non divergence calculation - with exposed pressure iteration control
• Overall new structure making the solver more similar to houdini's pyro solve
• In-built Wind Force, Turbulence Force, Buoyancy, and Drag Force

Version 3.0 Updates:

• Added the MacCormack advection model which has now because the solver default
• Exchanged the the Trace Mode drop down menu for an integer controlled 'Trace Steps'
• Removed the exposed pressure iteration control - is now locked at 50 iterations in solver
• Improved the multi-step non divergence calculation option - now an unlimited integer control
• Improved drag force
• Added a particle advect node

Explainer video to get you started:

https://www.youtube.com/watch?v=GmbANHNMDDk&ab_channel=AlbosX