Fluid simulation
Fluid simulation is an increasingly popular method in computer graphics to generate realistic simulations of water, smoke, explosions and the like. After configuring the parameters of the simulation and setting up the scene geometry, the simulator develops the movement of the liquid as a function of time using the (often considerably simplified) Navier-Stokes equations , which describe physically correct processes in Newtonian liquids and gases. In the field of computer graphics, the simulations occur in a wide range of application areas, starting with very rudimentary real-time animations for video games through to extremely computationally intensive effects for films.
method
There are numerous techniques for realizing these simulations. The most widely used are the Euler's grid-based method, the SPH method ( Smoothed Particle Hydrodynamics ) and the Lattice-Boltzmann method . They were created through research in the context of numerical fluid mechanics and have been continuously developed.
development
The earliest attempts in computer graphics to solve the Navier-Stokes equations were made in 1996 by Nick Foster and Dimitris Metaxas, whose work was mainly based on a 1965 work on computational fluid mechanics by Harlow & Welch. Based on her work, methods with techniques in smaller dimensions, such as 2D shallow water models and semi-random, turbulent noise fields, quickly emerged.
In 1999 Jos Stam published the so-called stable fluids method at the SIGGRAPH conference , which uses the semi-Lagrangian scheme and, with the direct integration of the liquid viscosity, produced unusually good results and also enabled much faster simulations. This technique was further developed by Ron Fedwik and his working group from 2001–2002 in order to enable even more complex 3D water simulations with the help of the level set method . In this context, an important developer to be mentioned are Ron Fedkiw, James F. O'Brien, Mark Carlson, Greg Turk, Robert Bridson, Ken Museth and Jos Stam.
software
There are a number of options for liquid simulation in standard 3D environments. A popular open source variant is Blender 3D with a relatively high-quality, implemented Lattice-Boltzmann method . Another popular option is Glu3d, a plug-in for 3ds Max that is very similar to Blender's simulation capabilities. There are also RealFlow , FumeFx , AfterBurn for Max, ICE SPH Fluids for Softimage or DPIT for Cinema 4D .