MODELING OF GAS PARAMETERS IN THE CYLINDER OF THE AUTOMATIC GUN DURING FIRING

The change of gas parameters in the cylinder of the automatic gun has a great influence on the dynamics of the gun. Many factors have an influence on the gas parameters in the gas cylinder such as the diameter and position of the gas port, the initial volume of the gas cylinder, the gap between the piston and the cylinder, initial temperature of the cylinder parts, etc. The analytical model was made to analyze the parameters on which depends gas piston dynamics. The numerical simulation with CFD software ANSYS Fluent was performed to analyze the change of the thermodynamic properties of the gases in the cylinder, temperature change of the cylinder parts and dynamics of the gas piston. The experiment was performed to provide pressures in the barrel and the gas cylinder and velocity of the gas piston. The comprehensive comparisons between results obtained by the analytical model, the numerical simulation and experiments have been performed and good agreements were observed.