The cloud (such as water cloud), which is formed by the inert substance suspending in the air, can prevent or suppress flame and shock wave′s propagation. Using a V-channel, water can be explosively dispersed to form water cloud, to get the aims of prevention or suppression of flame and propagation of shock wave. This paper presents the numerical simulation conducted on this process of explosive dispersion of water and formation of the water cloud. A comparison between the front trajectories of water cloud computed and the experimental data shows that the computed results are in good agreements with the experimented.