Hot-Spot Combustion of HMX

The combustion mechanism of pressed HMX samples is studied. It is shown that its combustion at pressures of 0.5 to 60 atm proceeds in the hot-spot mode. The dependence of the size of the hot spot on the average normal burning rate is obtained. The values of local combustion rates are estimated and the scatter range of their values is determined from the analysis of temperature distributions in time in the condensed phase of the combustion wave, obtained using thermocouples. Based on our own and published data, the so-called unambiguous (macrokinetic) dependence of the surface temperature on the combustion rate (the pyrotechnical law) is analyzed. This dependence is used to calculate the combustion surface temperatures corresponding to the scatter of local velocities, and it is shown that the scatter of the local velocities corresponds to the scatter of the combustion surface temperatures determined in the experiment, which indicates a hot-spot mechanism of HMX combustion.