Numerical simulation of the cooling process of TNT and Composition B explosives

Abstract

The present work numerically investigates the influence of the cooling method on the casting of TNT and Composition B explosives. The first approach uses a heating hood on top of the cylindrically shaped grenade to guide the solidification movement. The second method considers a heating probe inserted into the molten explosive. The numerical simulations were obtained using the enthalpy method in ANSYS Fluent software. The numerical verification was accomplished by comparing it with previously published studies. The results of the simulations for the solidification front and the temperature distribution are discussed. It was found that the solidification process using a heating hood leads to a higher portion of liquid explosive concentrate at the top, which could be an advantage compared to end processes in the middle of the explosive. Solidification using the probe heating method also showed the benefit of continuing melting the region above it while the probe is removed, which can prevent void formation. Finally, the explosive's thermophysical properties directly influence the solidification process's velocity. It was concluded that the cooling method using a heating probe takes a longer time to finish, which must be considered during the design of loading processes using the casting method.