Fluid modeling

There are several competing fluid modeling methods, each of which has its advantages and disadvantages. The most common are Euler grid methods, smoothed particle hydrodynamics (SPH ), turbulence methods, and the Boltzmann lattice equation method . These methods arose in the environment of computational fluid dynamics and were borrowed for practical tasks in the industry of computer graphics and special effects. The main requirement for these methods on the part of computer graphics is visual credibility. That is, if a human observer cannot see the unnaturalness of animation through viewing, then modeling is considered satisfactory. In physics, engineering and mathematics, on the other hand, the basic requirements are for physical correctness and accuracy of modeling, and not for its visual result.

In computer graphics, the earliest attempts to solve the Navier-Stokes equations in three-dimensional space were made in 1996 by Nick Foster and Dimitris Metaxas. Their work took as a basis the earlier work on computational fluid dynamics, which was published in 1965 by Harlow and Welch. Prior to the work of Foster and Metaxas, many fluid modeling methods were based on special particle systems , dimensional reduction methods (such as two-dimensional models of shallow water volumes such as puddles) and semi-random noise turbulent fields. In 1999, at SIGGRAPH, Jos Stam published the so-called Stable Fluids method, which used a semi-Lagrangian advection method and implicit viscosity integrations to ensure unconditionally stable fluid behavior. This allowed us to simulate liquids with a significantly larger time step and, in general, led to faster programs. Later, in 2001-2002, this method was expanded by Ron Fedkiv together with his staff, making it possible to process a complex model of water in a three-dimensional scene using the level set method .

The greatest contributors to fluid modeling were Ron Fedkiw , James O'Brien , Mark Carlson, Greg Turk , Robert Bridson ( born Robert Bridson ), Ken Museth ( born Ken Museth ) and Jos Stam ( born Jos Stam ).

Below is a set of the most famous and common software for modeling fluid.

• RealFlow is a computer program from Next Limit Technologies , originally designed exclusively for modeling liquids through SPH, but later expanded to model gases, solids and deformable bodies , etc. In 2007, RealFlow developers received an Academy Award for Technical Achievement from the Academy of Motion Picture Arts and Sciences for developing their program. ^[one]
• The free package for creating 3D graphics Blender contains an implementation of the stable method of lattice Boltzmann equations for modeling fluid. ^[2]
• Glu3d is a plugin for 3ds Max and Maya using SPH.
• AfterBurn is a popular 3ds Max plugin that, among other things, is capable of simulating fluid through a particle system.
• FumeFX is a 3ds Max plugin that simulates liquids, gases, flames and other phenomena. Based on the VoxelFlow internal technology, which uses incompressible Euler equations for mass and momentum conservation. ^[3]

English sources

• Fusion CI Studios, Fluid FX Specialists
• Flowline homepage
• Glu3d Homepage
• ICE SPH Fluids Homepage
• RealFlow Homepage
• Blender homepage
• Afterburn homepage
• Dynamite homepage
• DPIT Nature Spirit Homepage
• Ron Fedkiw's Homepage
• Berkeley Computer Animation Homepage
• Fluid Simulation for Video Games

Russian-speaking sources

• Leo Simonov "LEVel". Fluid modeling in 2D using a GPU (neopr.) 3. UralDev (February 24, 2009). Date of treatment August 15, 2011. Archived May 15, 2012.
• Sergey Koltsov, Julia Sazonova. Fluid modeling - from drop to ocean (neopr.) . Compuart magazine (No. 9 for 2008). Date of treatment August 15, 2011. Archived May 15, 2012.