The Potentials of Aluminium Nanoparticles: Novel High Energy Density Material for Underwater Explosions

Abstract

The destructive parameters of underwater explosives (i.e. shock wave energy, maximum pressure, and bubble radius) are limited to explosion heat; that is comparatively low. One approach for enhanced heat output can be accomplished by integrating reactive metal particles (i. e. Aluminium). However conventional aluminium particles (µm size) would contribute only with combustion gaseous products behind detonation wave front. Underwater, there is no oxygen for such contribution to take place. Furthermore, conventional Al particles could decrease the detonation velocity. So far, full exploitation of aluminium particles in underwater explosions has not been accomplished. Aluminium nanoparticles would combust more efficiently within detonation wave front, offering smaller critical diameter, high reaction rate, and high heat release rate. Consequently, Al nanoparticles could be ideal high energy density material for underwater explosion. Ship model with positive metacentric height, GMT = 4.7 cm for ship transverse stability, and GML = 19.3 for ship longitudinal stability was designed. Ship model offers large angle stability (heeling angles = 0-70 deg.). 2 g of explosive charge was detonated underneath the developed naval structure. Upon explosion, the acceleration of the naval structure was measured using shock accelerometer VC tri-axial, high frequency, 5000 ground acceleration, Dytran, Inc. While, Al particles (10 µm) offered an increase in mono-hull acceleration by 16 % compared to TNT; Al nanoparticles offered an acceleration increase by 49 %. This novel finding can be ascribed to the efficient combustion of Al nanoparticles within detonation wave front offering ideal detonation reaction with enhanced destructive effect.