A historical and current perspective on predicting thermal cookoff behavior

Prediction of thermal explosions using chemical kinetic models dates back nearly a century. However, it has only been within the past 25 years that kinetic models and digital computers made reliable predictions possible. Two basic approaches have been used to derive chemical kinetic models for high explosives: [1] measurement of the reaction rate of small samples by mass loss (thermogravimetric analysis, TG), heat release (differential scanning calorimetry, DSC), or evolved gas analysis (mass spectrometry, infrared spectrometry, etc.) or [2] inference from larger-scale experiments measuring the critical temperature (T-m, lowest T for self-initiation), the time to explosion as a function of temperature, and sometimes a few other results, such as temperature profiles. Some of the basic principles of chemical kinetics involved are outlined, and major advances in these two approaches through the years are reviewed.