Measurement of phase change and thermal decomposition kinetics during cookoff of PBX 9501

Dickson, P. M.; Asay, B. W.; Henson, B. F.; Fugard, C. S.; Wong, J.
April 2000
AIP Conference Proceedings;2000, Vol. 505 Issue 1, p837
Academic Journal
Models describing the kinetics of HMX slow decomposition in terms of reduced 3-step Arrhenius kinetics have been very successful in predicting time-to-explosion for HMX-based explosives over a wide range of heating rates. However, the detailed reaction and temperature profiles predicted by these codes have not been tested, and in particular, the accuracy of the predicted ignition location, which is thought to be an important factor in determining the subsequent reaction violence, is unknown. Experiments have been conducted to make spatially and temporally resolved temperature measurements in a cylindrical charge of PBX 9501 during external heating to cookoff. These data provide a direct comparison with the predictions of thermochemical models, and indicate that the existing models do not capture the detailed response of the process. The data have been used to develop a modified reduced kinetic scheme which models the process more accurately.


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