Computational and experimental study of detonation propagation in cylindrical TATB charges

The process of detonation propagation in a charge made of a plasticized explosive composition based on TATB in the form of a hollow cylinder with a steel shell inside is studied when normal detonation is initiated along a line on the outer surface of the charge. In experiments, the shape of the detonation wave (DW) front at certain points in time was determined using the X-ray method. Using electric contact sensors, the speed of propagation of the DW front along the outer surface of the charge was measured. The original setup of the experiments made it possible to study the propagation of detonation at angles greater than 180$^{\circ}$C from the initiation line. It is shown that in the initiation plane the front velocity of the diverging DW is $\approx$7.3 km/s. In the region of the “shadow” of the initiation point, the speed of the front of the diverging DW decreases depending on the distance traveled both along the outer surface of the charge – up to $\approx$6 km/s, and along the inner – up to $\approx$5.6 km/s. At the same time, near the steel shell in the region of rotation angles of the DW front from approximately 150 to 210$^{\circ}$C, a zone of unreacted TATB was recorded, which may indicate the disruption of detonation and its transformation into a shock wave. A numerical simulation of the process was carried out using the SURF detonation kinetics implemented in the MIMOSA technique. The calculation results are in good agreement with experimental data both at the early stage of the detonation initiation process and in the region of the “shadow” of the initiation point, where the velocity of the DW front decreases.