Establishment and simulation analysis on internal ballistics equations for artillery shrapnel

Abstract

Internal ballistic equations of artillery shrapnel are established on the basis of theoretical analysis, and equivalent method used for dealing with semi-combustible cartridge case, calculation program selects the Matlab software. The simulation results are accord with the experimental data, it shows design of equations and calculation program is reasonable and credible. Introductions With the requirements of development of artillery's technology, the emergence semi combustible cartridge case is a perfect combination of all advantages of combustible cartridge case and metal cartridge case. In this paper, we studied internal ballistic of lower chamber pressure artillery firing with semi-combustible cartridge case. According to the tactical technical requirements, in order to increase the damage effect of projectiles, launch projectiles need larger firing range and enough large falling angle when hit the ground target, so it must obtain different firing velocity. It is obviously that only one kind of charge cannot meet the requirements, and it must be spited into several small parts of propellant charge with different mass and shapes. But the propellant charge is incomplete combustion under low pressure when the charge is reduced to a certain amount, then the velocity distribution increased and the less quality of charge, the more obviously phenomenon. In order to address this issue the method of mixed charge is adopted that is combination of thin and thick powder charging gunpowder. In the small charging it mainly is thin charging gunpowder which can maintain constant pressure for complete combustion and fuse can remove insurance. Equivalent conversion for semi-combustible cartridge case For the convenience of calculation, equivalent method is selected for semi-combustible cartridge case in the calculation of internal ballistic that is release of energy in combustible cartridge case can burn for fixed value, converts it to a part of the ordinary powder, the semi-combustible cartridge case calculation can be used in the calculation method of the ordinary powder. In this paper, the ingredients of semi combustible cartridge case is same with the third generation cartridge case, the simplified physical model is shown in figure 1, and d is the outside diameter and h1 is the thickness of semi-combustible cartridge case. Material at the bottom of semi-combustible cartridge case is metal.