Critical Initiation Threshold of Covered Finite Thickness Explosive under Impact of Shaped Charge Jet

Abstract

AbstractThe compression depth of explosives is obtained on the basis of Lee penetration equation and the upper bound method to analyze the critical initiation threshold of finite thickness explosives. According to the pop curve, a theoretical model that reflects the relationship between critical initiation threshold and explosive thickness is established. Numerical simulation was carried out to simulate the initiation process and initiation threshold of explosives with different cover plate thicknesses. At the same time, we combine with the experimental data, to compare with the theoretical results. The calculations are in good agreement with data. Results show that the height of the bulge on the back of the cover plate and the compression depth of the explosive gradually increase with the thickness of the cover plate. When the cover plate reaches a certain thickness, there is no significant change on the final height of the bulge and the compression depth of the explosive. The decrease in explosive thickness increases the critical initiation threshold value, and the logarithm of the critical initiation threshold of the finite thickness explosive is approximately linearly related to the logarithm of the explosive thickness minus the compression depth. Therefore, this study can provide a reference for the initiation and simple calculation of the critical threshold of finite thickness explosives.