The influence of decouple coefficient(De), the center charge offset and shell weakening in one side on non-ideal characteristics of fuel dispersal were studied by using LS-DYNA. The calculation results show that the optimum value of De is 2 in this study. When the negative offset of center charge is 2 mm, the dispersal velocity in positive direction increases 6 m·s^-1 and decreases 13 m·s^-1 in negative direction. The more the negative offset of center charge increases, the more obvious the velocity increases in positive direction and decreases in negative direction, which indicates that the offset of center charge has inhibition effect at the same direction and promotion effect at the inverse direction on fuel dispersal. And when unilateral weakening occurs, the dispersal velocity of fuel in both sides decrease and the decrease of dispersal velocity in both sides of the Fuel-Air-Explosive (FAE) device using PVC shell is less than that of steel shell, which suggests the decrease of velocity is obvious when using high strength shell and slight with low strength shell.