FluidOS

FluidOS is a CFD (Computational Fluid Dynamics) program that uses LBM (Lattice Boltzmann Method.).. which is recently gaining more popularity in the CFD community and is subject of MANY scientific papers and university thesis, to simulate the interaction between fluids and fluids with solids in Single Phase or MultiPhase (2 components) environment.  It is mostly implemented in the GPU and it is ideal for "real-time" or "semi-real-time" analysis. LBM can also be implemented in 3D but so far I have only done 2D for Single phase and Multiphase in optional gravity field.

The intended audience for this project are students or researchers. This is NOT a game. However, you are welcome to play with it.  The project is still under development but you are welcome to try it and give me some feedback. Any recommendations are immensely appreciated.

And it is really meant for people that already know what LBM is (google it) and at a macroscopic level how it compares to the more traditional CFD methods using the Navier- Stokes Equations.  The purpose of the program is not to explain it but as a demo of it's potential use. LBM not only avoids the need to solve time-consuming Poisson Pressure Equation but also allows massive parallel calculations which is ideal for the GPU and for a real/semi-real time analysis. If you want to help with this development, please contact me.

The program starts with an empty  2D 'canvas' that you can resize before pressing 'Start'.  You can also set initial velocity and boundary conditions, air/liquid, single/multiphase. Once the simulation starts you can draw on the 'canvas' (solids, velocity or pressure sources)  change boundary conditions of Velocity or Pressure;  add obstructions and change fluid type (gas/liquid) and viscosity and density.  Viscosity controls the 'relaxation time'. Watch for instabilities, which usually are resolved by increasing viscosity or decreasing fluid speed. You can Plot X or Y cross section of the Velocity or Pressure profile. You can "Select" a solid area and the program automatically computes the Force vector exerted by the fluid.  You can save any situation to your hard drive and later retrieve to continue working on it. Units can be in Metric or English.

On "multiphase" I implemented 2 component Shan-Chen forces (interface interaction between fluids and fluid vs solids) and you can change the G parameters (similar to surface tension and miscibility). You can also change viscosity and relative densities for each component. I am still having some problems with the pressure gradient calculations when in multiphase mode, so please take the physical results with a 'grain of salt'. No guarantees there.

I do include a couple of examples in the distribution program that you can load via the File menu. And there is a small help for keyboard 'shortcuts' under Help menu but I have not written a detailed help. Hopefully the program interface is self-explanatory but let me know if it is not intuitive.

Minimum computer requirements: Windows OS, screen resolution 1440 x 1080 or better, and a decent GPU (whatever that means ... I have NVIDIA GeForce RTX 3070)

Thanks for downloading. Please 'like' it!

Contact papaysailor@gmail.com for more information or feedback.

See my other 'for fun' project here:

https://papaysailor.itch.io/archipelago-sailor-simulator