缓慢加热条件下壳装 PBX 炸药响应特性研究

To study the response law of ammunition under thermal stimulation, a slow cook-off test of PBX explosive in a shell was carried out and the heating rate was 1 K / min. The pressure-time curve inside the shell was obtained. The pressure change process inside the shell is divided into three sections: a section in which the pressure increases slowly due to the thermal decomposition of the explosive, a section in which the pressure increases rapidly due to the combustion of the explosive, and a section in which the pressure is maintained briefly when the shell breaks. A theoretical method is proposed to simulate the low-grade response of explosives in the shell during a slow cook-off. First, the Fluent software is used to calculate the temperature distribution of the explosive before ignition. It is assumed that a thermal decomposition reaction occurs in the region where the temperature is higher than the RDX decomposition temperature, and the RDX is consumed. The thermal decomposition coefficient k is introduced to describe the amount of the explosive where the thermal decomposition reaction occurred. On this basis, an improved interior ballistic equation set is established to describe the rapid rise of the internal pressure of the shell due to the combustion of the explosive, and the MATLAB program is compiled to perform iterative calculations on the equation set. The theoretical values and the experimental values are in good agreement. Then, using the calculated pressure-time curve as the input condition, the nonlinear dynamics software is used to simulate the fracture of the shell under the internal pressure. This method is used to calculate the thermal decomposition coefficients and pressure-time curves in the shell after ignition at different heating rates. The results show that when the heating rate is 1.0 K / min, the pressure growth rate after ignition is significantly higher than in other processes.