Detonation Propagation in 180° Ribs of an Insensitive High Explosive

Detonation propagation in 180° ribs of an insensitive high explosive has been studied using electrical pins. The ribs were 60‐mm thick and the sides were covered with steel plates. The outer radius was 60mm and the inner radius RI was varied from 30 to 50 mm. The inner and the outer edges were covered with PMMA or steel shells. The inner edge detonation velocity was found to be steady over the measuring range. After a transit region of 30 to 105° the difference between the times of detonation arrival at the outer and inner edges stabilizes at 0.2 to 2.3 μs depending on RI and the shell material. This implies the formation of the steady detonation regime where the whole reaction zone turns as a rigid body. The leading point of the front is situated 2 to 5 mm from the inner edge and travels at 0.9 to 0.98 of the steady detonation velocity depending on RI and the shell material. In the case of PMMA and RI=50 mm the detonation fails having turned at about 90°.