Thermal behavior of a high-energy material immersed in a fire

One of the uncertainties in the calculations of time-to-explosion for containers of high-energy materials immersed in fires is that of the thermal boundary at the container-explosive interface. Understanding this interface is critical in evaluating risks, safety issues and prevention mechanisms. In this work, the use of the Duhamel superposition method, coupled with measured internal temperatures, has shown that a 0.1m- diameter steel pipe containing PBX-9501 demonstrates similar thermal behavior when heated by either a propane fire or electricity. Similarly, the use of a transient heat transfer model has provided a great physical understanding of the system. For instance, the model predicted that a thermal contact resistance dropped the steel/explosive interface temperature by nearly 40%. The results are in agreement with an ignition model for HMX explosives.