HYDRODYNAMIC RAM IN FIGHTER JET AIRCRAFT FUEL TANKS: INVESTIGATION OF THE IMPACT OF TANK DEPTHS

Abstract

When a high-velocity projectile strikes a fluid-filled closed volume, it transfers its kinetic energy to the fluid, causing deformation to the surrounding walls, this phenomenon is known as hydrodynamic ram. This is a key concern in fuel tank design for both commercial and military aircraft. Hydrodynamic ram is crucial for vulnerability studies, particularly in fighter jet design, to determine failure points under impact. Numerical modeling with LS-DYNA’s ALE tool used in this study enables fluid-structure interaction simulations. Additionally, tank depth and filling levels influence hydrodynamic ram damage. To the best of our knowledge, the direct impact of fuel tank depth has not been thoroughly analyzed. This study compares two generic fuel tanks with identical dimensions except for depth, tested at different filling levels. Results indicate that shallower, more filled tanks are more vulnerable to hydrodynamic ram damage.