Apparent Intermediate Supervelocity of Detonation

Abstract

THE transition from the low to the high detonation velocity in a cylindrical dynamite charge is seen as a rather sharp bend in the streak camera curve. At the transition point the high velocity often starts with an apparent supervelocity which is much greater than the stationary high velocity. The reason is probably that the high velocity is initiated by the low velocity at a point on the axis. Good accordance between observed and calculated values is obtained if it is assumed that the high-velocity detonation sets off from a point a little behind the luminous zone of the low velocity. This accords with the fact that the latter, according to instantaneous photographs, is at the front of the preliminary reaction zone of Selberg and Sjölin¹.