Eng. Saeed Esmali Pourandarabi, Dr. Hossein Soury, Eng. Peyman Taghavi Eishkooh,
Volume 14, Issue 4 (12-2019)
Abstract
Detonation initiation by shock is an important issue in the explosive safety assessment and design of the explosive train and explosive devices. Experimental studies in this area are very difficult, expensive, and require advanced equipment. Therefore, simulation is a useful and suitable way for studying this phenomenon. The purpose of this article is to develop a one-dimensional computer code for simulation of the direct initiation of energetic materials. The Fortran SIN hydrocode, was used for this purpose and the I&G burn model was added to this code. The developed code was used to simulate the direct initiation of the Comp-B by sustained shock pulses. A good agreement was observed between the present simulation results and the results of other references. For example, in the simulation of the initiation of Comp-B by 3.78 GPa shock, the run distance to detonation was 14.8mm, which the difference between this value and the reported experimental data is 5.7%.
Mohsen Rouhbakhsh, Saeed Tavangar, Seyyed Mohammad Reza Sedighi Saber, Seyyed Hadi Motameshariati, Mohammad Hossien Ghezel Ayagh,
Volume 18, Issue 2 (9-2023)
Abstract
In addition to the inherent characteristics of explosives, the power of the detonation is affected by arrangement of the explosive train. Therefore, the correct design of the explosive train, especially for insensitive explosive charges containing aluminum, play a fundamental role in order to be more effective. In the current research work, by changing the dimensions of the booster pellet and its position relative to the main charge; the detonation behavior of the main charge has been investigated. In this study, the booster pellet (COMP-A3) is modeled with JWL equation of state and the main charge (PBXN-111) is modeled with ignition and growth equation of state. The simulations has been done using AUTODYN software. The coefficient used in the equation of state (ignition and growth) has been evaluated with experimental results. The simulation results show that by reducing the diameter of the booster pellet from 5cm to 3cm, for a certain length of the booster pellet, reaching to the steady detonation increases due to the greater divergence of pressure wave into the charge. In the case where the booster is inside the charge, the peak pressure values increase in the corners of the charge and adjust the pressure drop due to the divergence. The simulation shows that for the case where the booster and the main charge are placed on top of each other, the booster with a diameter of two centimeters with any length of the booster pellet is not able to create stable detonation in the main charge. For a submerged condition of the same diameter, the booster can produce stable detonation in the main charge. This study showed that a booster pellet with a diameter of 5 cm and a length of 4 cm can cause a complete detonation in PBXN-111. The length of the region to reach stable detonation with this booster is 15 cm.
