Abstract: A self-ejection launcher is proposed to solve the negative influence of exhaust plume on the surrounding equipment and perssonel. The exhaust plume generated by self-ejection launcher is sealed in a low pressure chamber until the tail leaves the launcher barrel. In order to study the characteristic and rules of interior ballistic of self-ejecting rocket projectile, a solution model of internal ballistic of self-ejecting rocket projectile was developed based on the classical interior ballistic. Physical tests of 5 rocket projectiles were carried out under three working conditions, i.e., low pressure chamber with initial length of 300 mm, low pressure chamber with initial length of 300 mm and two holes with pore diameter of 15 mm on it, and low pressure chamber with initial length of 150 mm. Compared with the experimental data and simulated data,the curves of the pressure in low pressure chamber have good consistency. The maximum relative error of the peak of pressure in low pressure chamber and the instantaneous velocity of the missile leaving the launcher are 9.29% and 5.24%, respectively, and the validity of interior ballistic model is verified. The influences of the trepanning on low pressure chamber, the length of low pressure chamber, the length of launcher ,the mass flow rate of motor on the interior ballistic of self-ejecting rocket projectile are ananlyzed based on the interior ballistic model.

Key words: rocketprojectile, self-ejection, interiorballistic, Runge-Kuttamethod, numericalanalysis