Approximate Method of Calculating Critical Shock Initiation conditions and run distance to detonation

An approximate model for pressure buildup behind the front of an initiating shock wave is developed. This model leads to the widely used P2t initiation criterion, but the pressure index is not limited to a value of two. Expressions for wave run time and distance to detonation are also obtained. The use of the model is illustrated using explosives widely discussed in the literature. It is shown that critical shock initiation and run distance to detonation can be rapidly estimated to good approximation over a wide range of shock conditions from the results of one or two relatively simple experiments. The calculational method may be useful for various applications.