Numerical simulation and experimental study of flowfield around a bullet with a partial core

The geometry, density and velocity of a typical small caliber bullet, are the main factors that stabilize its flight path, range and the impact force; thus the weight variations can indicate the presence of geometrical irregularities or damages of the bullet core, affecting its dynamic characteristics. Computational finite element method (FEM) with the computational fluid dynamic (CFD) module was used for the numerical simulation of 7.62 mm bullets with partial core, subjected to different air flow conditions. Schlieren images were obtained and with the flow visualization principle, the behavior of the projectile during its flight path was determined. The results of the simulations and the experiments showed that in certain cases, bullets with partial core maintain a stable spin during flight without a considerable variation in its range, keeping constant speed conditions with respect to the full core bullets. The importance of this analysis is found in the fact that post processing activities can be implemented in certain ammunitions with imperfections to improve their use.