Uses For Variable Velocity BulletsPolice officers armed with a weapon developed at the Oak Ridge National Laboratory (ORNL) will be able to dial up the velocity of the bullet depending on the situation and the intent of the shooter. Using a cartridge based on the standard shotgun shell, Rusi Taleyarkhan and colleagues have harnessed the power of vapor explosions to allow projectiles to stun, disable or kill.
Variable Velocity Bullet Inventor Rusi TaleyarkhanThe propellant in the cartridge takes advantage of the explosive interaction between aluminum and water. Molten aluminum reacting with water can produce up to three times the energy of high explosives. For years, ORNL's Rusi Taleyarkhan studied the potential problem of steam explosions in water-cooled research reactors in which fuel elements are made of uranium-aluminum alloys sandwiched between aluminum plates. The concern was that an explosion might result from the interaction between heated molten aluminum and water in a research reactor, such as ORNL's High Flux Isotope Reactor, during severe accident conditions (an unlikely event that, nevertheless, has occurred in similar reactors elsewhere). Taleyarkhan led an investigation of the forces that could initiate, or trigger, an explosion and the nature of its propagation.
Further research demonstrated that introducing noncondensable gases into the protective steam film formed by aluminum-water contact would cushion external triggers, virtually eliminating the conditions that initiate melt-water explosions. This key finding is being confirmed by field tests of methods for preventing explosions in the aluminum industry.