Simulation of Bullet Fragmentation and Penetration in Granular Media

Area of Science:

• Materials Science
• Physics
• Engineering

Background:

• Understanding projectile behavior in granular media is crucial for defense and safety applications.
• Simulating bullet-material interactions requires accurate modeling of granular dynamics.

Purpose of the Study:

• To simulate and experimentally validate bullet fragmentation within granular media (sand).
• To assess the kinetic energy dissipation capabilities of sand during projectile impact.

Main Methods:

• Numerical simulation using the smooth particle hydrodynamics (SPH) module in ANSYS AUTODYN.
• Experimental validation using two box prototypes (fiberglass and plywood) with sand subjected to bullet impacts.
• X-ray photography to determine bullet penetration depth.

Main Results:

• Experimental results showed a significant reduction in bullet kinetic energy from 2750 J to 100 J within 0.8 ms.
• Numerical simulations closely matched experimental observations, particularly regarding penetration depth.
• Observed bullet fragmentation upon impact with the sand medium.

Conclusions:

• Sand effectively dissipates kinetic energy from impacting bullets.
• The smooth particle hydrodynamics (SPH) method accurately simulates bullet-sand interactions and fragmentation.
• The study confirms the potential for granular media to mitigate projectile impact energy.