高速旋转弹丸炸药装药在膛内运动中底层温度的数值模拟

This paper concerns on the safe launch of high-speed spinning projectile filled with pressed charge. A calculation model for the the variation in temperature of explosive charge due to friction in in the moving process in bore is established based on the theory of friction heating, heat transferring and temperature rising. A crash accident of a highly rotating projectile occurring after it exits from the muzzle is taken for an example. The model parameters, including the pressure on the bottom of charge, and the relative angular velocity of charge and projectile body, were obtained by using LS-DYNA software to simulate the internal ballistic process of projectile, and MATLAB was used to obtain their specific function form. The variation in temperature of explosive charge in the moving process in bore was culculated. The results show that an obvious relative rotation of charge and projectile body occurs when the environment temperature reaches to 50℃. Hence, an amount of heat is generated from the strong friction of charge and projectile body at the bottom of explosive charge. Part of the heat is transmitted to and warms the charge so that the highest temperature is 302.3℃ at the bottom of charge, which is much higher than the thermal decomposition temperature. A large number of hot spots are generated on the charge surface and grow rapidly in the confined space, finally causing exploding.