PREDICTING RUNAWAY REACTION IN A SOLID EXPLOSIVE CONTAINING A SINGLE CRACK

This work predicts the critical conditions required for the onset of reaction runaway in a narrow high‐explosive slot intended to simulate a crack. We review ongoing experiments where flames propagated through such slots at velocities up to 10 km/s, reaching pressures in excess of 1 kbar. A model is developed where slot pressurization is attributed to gas‐dynamic choking at the slot exit. The combination of choking and a pressure‐dependent reaction rate is shown to be capable of runaway reaction for a range of slot dimensions and pressures. This model agrees with experimental pressure measurements of reaction runaway in slots and provides a mechanism for the erratic burning observed with some explosives under high pressure.