Effect of eccentricity and obliquity on the ballistic performance and energy dissipation of hemispherical shell subjected to ogive nosed

摘要

A numerical study was undertaken to investigate the effect of projectile eccentricity and obliquity impact on the ballistic performance of the Aluminium 1100-H12 1 mm thick hemispherical shell against ogive nose projectile. The projectile eccentric distance was taken with respect to the radius of the shell such as 0th, R/4th, 2R/4th and 3R/4th whereas, the incidence angle of the projectile as 0?, 15?, 30?, 45?, and 60? for each shell (68, 100, 150 and 200 mm diameter). The projectile was impacted at different velocities for each incidence angle and eccentric distance and ballistic limit obtained. Three-dimensional finite element simulations were carried out by using the Abaqus/explicit solver. Johnson cook material model was used to simulate the behaviour of a hemispherical shell. The results of the numerical study were elucidated through the experimental result conducted for normal impact. Moreover, user-defined coding written in python was used to obtain the energy dissipation in different stretching mode. The result showed that the ballistic performance of the target was influenced by both the eccentricity and obliquity. Also, the target was failed in ductile hole enlargement with petals formation however, the number of petals form was depended upon the eccentricity and obliquity.