The Simulation Of Ink In Water Animation Based On Particle System

The motion of ink in water is a new form of art. According to the traditional Chinese ink,it changed the way to draw pictures on painting paper. Instead, because of the viscosity of ink,it shows the artistry of ink diffusing in water. Nowadays, both in the photography and in themedia broadcasts, the animations of ink in water have been used more and more widely. It hasbecome a new way for media communication. And more and more people show their interestin it.We propose a method using particle system, the motion differential equation ofincompressible viscous fluid from fluid mechanics (Navier-Stokes Equations) and theBrownian motion to simulate the diffusion of ink in water.First, we analyze the method of fluid simulation and irregular motion. And we alsodiscuss the principle of the particle system. Ink and water are defined as two kinds of fluids.Ink is defined as a finite set of particles with definite attributes. Water is defined as spacebackground. Water space is full of ink particles by the continuous or discrete way. Based onthis theory, we define the initial attributes of the ink particles, including the generation, thestate of the motion and so on. Next, the Navier-Stokes Equations are used for the motion ofink in water. And the solution of N-S equations is simplified by four steps. The velocity ofeach ink particle is solved by external force, convection, viscosity of the fluid and thecompressive stress. Because of the characteristics of the charcoal particles in ink that theirmotion is a continuous-time stochastic process, we use the Brownian motion to get the finalresult of the motion.The simulation of ink in water is worked on VC++2008platform with OpenGL and themotion model above. This experiment shows that it is an effective method to simulate thediffusion of ink in water in real time.