摘要：The present study is devoted to researching the thermal security problems of large-scale solid rocket motor with Ammonium perchlorate/Hydroxyl-terminated polybutadiene (AP/HTPB). A two-dimensional axisymmetric model for the cook-off of solid rocket motor is established. The reaction kinetics for the cook-off process of AP/HTPB is described by the two-step global chemical mechanism. Numerical predictions of the cook-off behavior for the propellant are conducted at fast heating rate of 1.45–2.45 K/s, and slow heating rate of 0.001–0.003 K/s, respectively. The results show that in the fast cook-off condition, the initial ignition position of AP/HTPB occurs in the annular region of the outer wall of propellant without exception, and the center point in the region is (889.1, 149.5). For the region, the axial width is 1.8 mm and radial thickness is 0.8 mm. However, in the slow cook-off condition, the ignition center position is shifted along the axial direction toward the right end face of the propellant with the increase of heating rate. Therefore, the influence of heating rate on ignition temperature and ignition delay time is nonnegligible within a certain range.
