AN OPTICAL INVESTIGATION OF DETONATION

The experiments described here were undertaken with the purpose of measuring the length of the detonation zone in several typical explosives of the military type. To obtain a sharp photograph of a moving zone of detonation, each image was rendered stationary at the film by a rotating mirror. The self-luminosity recorded in such photographs indicates a detonation zone of length 0.2 to 0.5 mm for all compositions tested; lengths generally reports in the literature are greater than this, usually from 1 to 10 mm. Using an original scheme, the velocity of detonation was measured for each composition; this velocity was needed before photographing each stationary image