CFD Simulation of the Gas-Operated Weapon Drive Applied to the UK-59 Machine Gun

The flow characteristics of propellant gases inside the gas cylinder of the weapon gas-operated mechanism, applied to the UK-59 machine gun, are studied. Computational Fluid Dynamics (CFD) in ANSYS Fluent is used for the simulation of flow through the gas port from the barrel bore to the gas cylinder and back. The study's findings are presented along with the piston law of motion and thermodynamic quantities of gases inside the cylinder, specifically the pressure, temperature, and velocity distribution of gases in the cylinder for various piston displacements. The experiment was carried out to specify the pressure of the gases in the cylinder, as well as the displacement of the piston. The experimentally obtained values are compared to the simulation results with a very good agreement.