Fluid animation has recently become more popular and it is widely used in industrial fields

like movies

animation

and games. Because of the complexity of its movement

various methods have been presented to produce visibly pleasing effects. The commonly used simulation methods are velocity based methods. However

they suffer from fast loss of fluid details. In order to maintain details in the simulation process

vorticity based methods produce many impressive effects. However

they suffer from serious problems when considering boundaries and the problem of stability. Our goal is to produce methods to get rid of these drawbacks. We use vortexes to represent the vorticity of the domain. Similarly to other vortex methods

we also do convection

stretching and adding body force. However

we use a new grid to compute the velocity. With this new grid structure

we stagger the different components of vorticity on the center of edges of each voxel. This grid structure is highly compatible with the commonly used grid structure

which staggers the different components of velocity on center of faces of each voxel. Using this grid structure

we can easily cope with different boundaries including solid boundaries and free surfaces

and we can easily enforce incompressibility in one voxel. We present several scenes of smoke animation to represent the capability of our method to cope with different boundaries. Moreover

we also present a chart about the energy changing process in these scenes with fixed vortexes with an initial vorticity vector. Furthermore

we neglect the body force in this experiment. The chart shows that our method is very stable and the amplitude of the energy wave is less than 0.005%. We present a new vortex method with a new grid structure. Byusing this new grid structure

our method can process with different boundaries

including solid boundaries and free surface. Moreover

the results show that our method can preserve fluid details in the simulation process and it is very stable.