Natural convection effects on TNT solidification inside a shaped charge mold  

作　　者：Cigdem Susantez Aldelio B.Caldeira Bruna R.Loiola 

机构地区：[1]Trakya University,Engineering Faculty,Mechanical Engineering Department,Edirne,22030,Turkey [2]Management and Technological Innovation Agency,Brazilian Army,Rio de Janeiro,23020-470,Brazil [3]Military Institute of Engineering,Mechanical Engineering Department,Rio de Janeiro,22290-270,Brazil

出　　处：《Defence Technology（防务技术）》2022年第9期1653-1661,共9页Defence Technology

摘　　要：High Explosive Anti-Tank(HEAT) warheads and ammunitions are frequently produced by explosive casting inside an axis-symmetric mold with an inverted conical geometry in the basis. In order to prevent manufacturing defects, the solidification process must be controlled. In this study, a dimensionless solidification model has been proposed to investigate the heat transfer considering the natural convection inside the liquid explosive and the numerical simulations were performed by using COMSOL Multiphysics and Modeling Software, employing trinitrotoluene(TNT) thermophysical properties. The effect of three different boundary conditions on the top of the mold have been evaluated: convection, adiabatic and isothermal. It has been observed that solidification process was faster for convection case and slower for isothermal case, while an intermediary total solidification time value was found for adiabatic case.Moreover, liquid explosive was completely surrounded by solid explosive during the solidification process for convection case and also for adiabatic case through the end of the process. Otherwise, it was not observed for isothermal case. The natural convection effects promoted a vortex inside the liquid explosive, accelerating the heat transfer process. It has been concluded that isothermal mold top boundary condition should be preferred to prevent manufacturing defects, avoiding high thermal stress.

关 键 词：SOLIDIFICATION Natural convection Explosive Dimensionless model Anti-Tank ammunition 

分 类 号：TJ410.52[兵器科学与技术—火炮、自动武器与弹药工程]