Study On The Detail Enhancement For Smoke Simulation

Physically-based fluid simulation is always one of the hot research topics in computergraphics. Due to its important application value, smoke simulation is the focus ofrecent research. It was widely applied in game engine, special effects of movie,simulation of disaster scene, etc. A key point of smoke simulation is to perform richdetails and make the smoke more plausible. This paper is mainly established themethods for the detail enhancement of smoke simulation.This paper proposed a detail enhancement method which is based on thetwo-scale gird. We designed an adaptive un-uniform grid division scheme. Thisscheme can lead to a good detail and reduce the huge computation cost compared withthe traditional uniform grid based methods. We simulated the smoke on the coarsegrid first. Then, we divided the coarse grids which need enhancing detail into fine grid.After that, add vorticity confinement force to the velocity field of fine grid to enhancethe detail. Finally, obtain the final velocity field by sampling from the fine grid. Whencalculating the vorticity confinement force to add turbulence in the fine grid, weconsidered the helicity and energy cascade. Considering helicity can avoid “blow up”and artificial phenomenon when the vorticity confinement parameter is too high.Considering energy cascade can make the simulation more physically. Experimentsshow that this method can obtain better results.Based on the wavelet transform theory, we proposed a method of decomposingthe velocity filed in the wavelet domain to add turbulence detail. We simulated thesmoke on the coarse grid first. Then, interpolate the velocity from coarse grid to thefine gird and wavelet transform it. Inspired by the wavelet transform based imagefusion method, we fused the velocity field of coarse and fine grid in the waveletdomain to improve the effect of interpolation. After that, add vorticity confinementforce to the high frequency direction in the high frequency part of the wavelet domainto enhance the detail of smoke. Finally, taking inverse wavelet transform to obtain thefinal velocity filed. By comparison with other methods, it shows that this methodenhances the details while improving the simulation efficiency.