3.2.1.1. Stage I: expansion of the explosive

The expansion of the explosive starts at the point of detonation (central point of the top surface of charge), as shown in Figure 14. The detonation of a high-performance explosive is achieved by compressing and heating of its constituents, resulting that a chemical reaction is triggered and then it is supersonically propagated through the explosive at the Chapman-Jouguet velocity. Whereafter, a strong shock wave, generated by the violent expansion of the gaseous products, propagates into the ambient medium. Since the sound speed increases with the increased temperature in the compressible flow, shock waves are generated. The detonation wave generated by the cylindrical charge presents an obvious directionality and a cross distribution shape. The axial propagation speed is larger than the radial propagation speed, so the axial pressure is also greater than that of radial direction due to the proportional relationship between the wave speed and intensity in air medium.

Figure 15. A typical process of explosive product-structure interaction.

Single-Curvature Sandwich Panels with Aluminum Foam Cores under Impulsive Loading

http://dx.doi.org/10.5772/intechopen.70531

133

Figure 14. A typical process of the charge detonation.

Single-Curvature Sandwich Panels with Aluminum Foam Cores under Impulsive Loading http://dx.doi.org/10.5772/intechopen.70531 133

Figure 15. A typical process of explosive product-structure interaction.

Figure 14. A typical process of the charge detonation.

132 Contact and Fracture Mechanics
