Fluid animation refers to

computer graphics Computer graphics deals with generating images and art with the aid of computers. Computer graphics is a core technology in digital photography, film, video games, digital art, cell phone and computer displays, and many specialized applications. ...

techniques for generating realistic animations of fluids such as water and smoke. Fluid animations are typically focused on emulating the qualitative visual behavior of a fluid, with less emphasis placed on rigorously correct physical results, although they often still rely on approximate solutions to the

Euler equations In mathematics and physics, many topics are eponym, named in honor of Swiss mathematician Leonhard Euler (1707–1783), who made many important discoveries and innovations. Many of these items named after Euler include their own unique function, e ...

Navier–Stokes equations The Navier–Stokes equations ( ) are partial differential equations which describe the motion of viscous fluid substances. They were named after French engineer and physicist Claude-Louis Navier and the Irish physicist and mathematician Georg ...

that govern real fluid physics. Fluid animation can be performed with different levels of complexity, ranging from time-consuming, high-quality animations for films, or visual effects, to simple and fast animations for

real-time Real-time, realtime, or real time may refer to: Computing * Real-time computing, hardware and software systems subject to a specified time constraint * Real-time clock, a computer clock that keeps track of the current time * Real-time Control Syst ...

animations like computer games.

Relationship to computational fluid dynamics

Fluid animation differs from

computational fluid dynamics Computational fluid dynamics (CFD) is a branch of fluid mechanics that uses numerical analysis and data structures to analyze and solve problems that involve fluid dynamics, fluid flows. Computers are used to perform the calculations required ...

(CFD) in that fluid animation is used primarily for visual effects, whereas computational fluid dynamics is used to study the behavior of fluids in a scientifically rigorous way.

Development

The development of fluid animation techniques based on the

began in 1996, when Nick Foster and Dimitris Metaxas implemented solutions to 3D Navier-Stokes equations in a computer graphics context, basing their work on a scientific CFD paper by Harlow and Welch from 1965. Up to that point, a variety of simpler methods had primarily been used, including ad-hoc particle systems, lower dimensional techniques such as height fields, and semi-random turbulent noise fields. In 1999, Jos Stam published the "Stable Fluids" method, which exploited a semi-Lagrangian advection technique and implicit integration of viscosity to provide unconditionally stable behaviour. This allowed for much larger time steps and therefore faster simulations. This general technique was extended by Ronald Fedkiw and co-authors to handle more realistic smoke and fire, as well as complex 3D water simulations using variants of the level-set method. Some notable academic researchers in this area include Jerry Tessendorf, James F. O'Brien, Ron Fedkiw, Mark Carlson, Greg Turk, Robert Bridson, Ken Museth, and Jos Stam.

Software

Many 3D computer graphics programs implement fluid animation techniques. RealFlow is a standalone commercial package that has been used to produce visual effects in movies, television shows, commercials, and games. RealFlow implements a fluid-implicit particle (FLIP; an extension of the

Particle-in-cell In plasma physics, the particle-in-cell (PIC) method refers to a technique used to solve a certain class of partial differential equations. In this method, individual particles (or fluid elements) in a Lagrangian frame are tracked in continuous ...

method) solver, a hybrid grid, and a particle method that allows for advanced features such as

foam Foams are two-phase materials science, material systems where a gas is dispersed in a second, non-gaseous material, specifically, in which gas cells are enclosed by a distinct liquid or solid material. Note, this source focuses only on liquid ...

and spray.

Maya Maya may refer to: Ethnic groups * Maya peoples, of southern Mexico and northern Central America ** Maya civilization, the historical civilization of the Maya peoples ** Mayan languages, the languages of the Maya peoples * Maya (East Africa), a p ...

and

Houdini Erik Weisz (March 24, 1874 – October 31, 1926), known professionally as Harry Houdini ( ), was a Hungarian-American escapologist, illusionist, and stunt performer noted for his escape acts. Houdini first attracted notice in vaudeville in ...

are two other commercial 3D computer graphics programs that allow for fluid animation.

Blender A blender (sometimes called a mixer (from Latin ''mixus, the PPP of miscere eng. to Mix)'' or liquidiser in British English) is a kitchen and laboratory appliance used to mix, crush, purée or emulsify food and other substances. A stationary ...

is an

open-source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use and view the source code, design documents, or content of the product. The open source model is a decentrali ...

3D computer graphics program that utilized a particle-based Lattice Boltzmann method for animating fluids until the integration of the open-source mantaflow project in 2020 with a wide range of Navier-Stokes solver variants.

References

External links

RealFlow Homepage

Blender Homepage

Berkeley Computer Animation Homepage
{{Computer graphics 3D computer graphics Computational fluid dynamics

Relationship to computational fluid dynamics

Development

Software

See also

References

External links