基于流体动力学的火焰实时绘制技术

Real-time fluid-dynamic-based fire modeling and rendering technology

为了实时有效地渲染真实的火焰,引入了基于流体动力学的气体建模方法和分形插值技术,在粗网格下采用半拉格朗日方法和隐式差分格式,直接求取火焰的纳威-斯托克斯方程,这种数值解法在粗糙网格、大的时间步下也能无条件稳定,能达到实时渲染的目的。在细网格下,为了渲染湍流火焰,采用分形插值的方法,增强湍流火焰的边缘细节。实验结果表明:该方法实现简单,仿真速度快,显示的动画效果真实,并且是无条件稳定的。

A fast and interactive method is proposed for simulating and controlling the fire animation effectively. This method is based on fluid dynamics and fractal interpolation. First, the fire animation is simulated by solving the fundamental equations governing fluid flow, commonly known as the Navier-Stokes equations. An unconditional stable fluid solver is used to solve the Navier-Stokes equations in coarse grid. The semi-Lagrangian characteristic tracing technique is used to advect the velocity, density and temperature. The implicit scheme is used to diffuse the velocity, density and temperature. Then in fine grid fractal interpolation is used to add the detail. The results show that it was an efficient method for interactive simulating highly detailed fire. Also. it was fast and unconditional stable.