Experimental Validation of Detonation Shock Dynamics in Condensed Explosives*

Experiments on the HMX-based, condensed explosive PBX-9501 were carried out to validate a reduced asymptotically derived description of detonation shock dynamics (DSD) where it is assumed that the normal detonation shock speed is determined by the total shock curvature. The passover experiment has an embedded lead disk in a right circular cylindrical charge of PBX-9501 and is initiated from the bottom. A range of dynamically changing states, with both divergent (convex) and converging (concave) shock shapes are realized as the detonation passes over the disk. The time of arrival of the detonation shock at the top surface of the charge is recorded and compared against the DSD simulation and a separate multi-material simulation (DNS). A new wide- ranging equation of state (EOS) and rate law is used to describe the explosive and is employed in both the theoretical (DSD) calculations and the multi-material simulations. The experiment, theory and simulation are found to be in excellent agreement.