Experimental Research on the Launching System of Auxiliary Charge with Filter Cartridge Structure

A launching system with a filter cartridge structure was proposed to improve the muzzle velocity of the projectile. The combustion chamber of the launching system is divided into two fixed chambers, one is located in the breech chamber, and the other is arranged in the barrel. The breech chamber charge was ignited first, and the charges in the auxiliary chambers were ignited by the high-temperature, high-pressure combustible gas trailing the projectile. In this way, the combustible gas in the auxiliary chambers could compensate for the pressure drop caused by the movement of the projectile. The proposed device features the advantage of launching a projectile with high muzzle velocity without exceeding the maximum pressure in the chamber. In order to obtain some internal ballistic characteristics of the launch system, some critical structure, such as the length of the filter cartridge auxiliary charge, the combustion degree of the propellant in the chamber, and the length of the barrel, are discussed. The experimental results show that with the increased auxiliary charge length, a pressure plateau or even a secondary peak pressure can be formed, which is less than the peak pressure. The projectile velocity increased by 23.57%, 14.64%, and 7.65% when the diaphragm thickness was 0 mm, 1 mm, and 2 mm, respectively. The muzzle velocity of the projectile can be increased by 13.42% by increasing the length of the barrel. Under the same charge condition, with the increase of barrel length, the energy utilization rate of propellant increases by 28.64%.