Study On Charge Technology Of Smokeless Aerial Shell

The new smokeless propellant (spherical propellant with micro pores) is an environmental propellant, and it was produced from expired propellant. Compared to black powder, the smokeless propellant is a propellant with higher energy, larger specific volume and less combustion residue. In order to overcome the drawback of black powder, and provide a direction for dealing with the obsolete propellant and a guide for the safety burning of the aerial shell, the feasibility to substitute the spherical propellant for black powder was analyzed based on the traditional aerial shell charging and the energy-design theory of propellant. Combined with the theory of interior ballistic and charging design, the influence of charge weight and charge mode on the aerial shell launch velocity and the laws of energy releasing in the process of launching were investigated. And the effect of the charge weight, shell strength and charge structure to the laws of energy releasing of the aerial shell were also studied. The results show that the pressure in the chamber rises, and the velocity increases with the propellant charge increased. And the exploding pressure of the aerial shell increases with the increase of the charge amount and improve of the shell strength. The modularized charge is useful to solve the problem of combustion residue, and increase the utilization rate of spherical propellant. The explode height and radius of aerial shell was measured by surveyor's pole method. The experimental results show that to substitute the spherical propellant for black powder was feasible. Based on external ballistics theory, the process of fireworks explode was analyzed, and a mathematical model of aerial shell explode with the idealized conditions was established. Through numerical simulation, it was found that the computational result is accords with the general law of aerial shell explosion. The laser transmittance rate of the combustion production of the smokeless aerial shell was measured in smoke box. The results show that the laser transmittance rate of the spherical propellant is two times more than that of the black powder, and to use the spherical propellant can reduce the impact of smoke on the viewing effectively of fireworks.