An analytical model for ballistic impacts against ceramic tiles

An improved analytical model able to simulate normal ballistic impacts of blunt shaped equivalent projectiles against ceramic tiles, without any backing plate, is described. The projectile is modelled as a rigid body with a deformable tip that can be eroded when in contact with the ceramic, that in turn is eroded and comminuted when critical conditions are reached. The modified Bernoulli equation relates the velocities of the deformable projectile and the ceramic assuming a hydrodynamic behaviour of the parts in contact, in proximity of the impact area. Innovative contributions are added in order to reproduce also low velocity impacts (below the Bernoulli limit), a range in which the modified Bernoulli equation can't be applied. The model is compared with experimental data both from the literature and from ballistic tests, with actual bullets, performed by authors, predicting the residual velocity and the residual mass of the projectile (when the data is available), with also an analysis of the evolution in time of the parameters.