To analyze the impact of VESF on Jetting Projectile Charge(JPC) formation, nonlinear dynamics analysis software AUTODYN-2d was used for numerical simulation. The simulation results of penetrator formation were obtained with different VESF materials, shapes(K shape, rectangular, triangular) and the distance between VESF and main charge. Results show that the main charge initiation point transfers from center to outside gradually with the increase of VESF material density and the distance between VESF and main charge. Different initiation modes are formed with different transverse shapes of VESF, and it is a point initiation for K shape and rectangle, and the plane initiation for triangle. The optimum conditions to JPC formation are: steel plate, K shape and 6 mm (distance from VESF to charge).