Based on the cylindrical smoking device, the Truegrid simulation software was used to establish a cylindrical shell mesh model with a"V"groove. The simulation model of the smoking device was established by Autodyn software, and the variation law of the detonation pressure during the initial cloud explosion and dispersion process of the smoke screen was numerically simulated. With the help of the piecewise linear interpolation function provided by MATLAB, the pressure as a known quantity was introduced into the explosion dispersion theory model, and the model was numerically calculated by the Euler method. Field test experiments were carried out, and experimental data were obtained using camera method and image processing technology. The results show that the time occurring the first stage of explosion dispersion is from 0 to 8.9×10^-6 s, and the maximum radius of the initial smoke cloud increases by 3 to 4 times that of the original. In the second stage of the explosion dispersion, the maximum radius of the initial smoke cloud increases to about 3 m. Based on the mixed simulation of Truegrid and Autodyn and combined method with the theory of explosion dispersion theory, the calculation error of the maximum radius of the initial smoke cloud is reduced by 3%~8% compared with the traditional theoretical method of solving the explosion dispersion model by numerical integration alone. The maximum radius of the initial smoke cloud is closer to the experimental result than the single theoretical model method. The convergence of calculation model of the Euler method is better than that of the fourth-order Runge-Kutta method.