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

Abstract

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.

Mathematical Model of Automatic Firing System of Gas-Operated Machine Gun

“…The numerical integration method was used to solve the system of equations (21). The 4 th -order Runge-Kutta method was implemented in the Matlab R2022b programming environment.…”

“…For the above reasons, there have been a large number of documents, studies, and simulation tools that have been used by previous researchers to research, design and optimize automatic firing systems. Some of the most notable documents are [12][13][14][15][16][17][18][19][20][21][22][23]. However, the problem of calculating the dynamics of automatic firing systems of gasoperated weapons has not been studied methodically and fully.…”

“…In recent years, the method of numerical integration has been widely used by many researchers and has obtained many remarkable achievements, [14][15][16][17]. Besides, the calculation of fluid dynamics (CFD) has been interesting and applied by many researchers to study and analyze the gas flow through the gas port hole, [18][19][20][21]. However, these studies have not completely solved the dynamics of the automatic firing system.…”

“…However, these studies have not completely solved the dynamics of the automatic firing system. Some studies have only solved this problem in the backward movement stage of the bolt carrier, [14,15,17,[20][21]. Notably, the experimental method has also been used to determine the dynamic parameters of the automatic firing system, refer to [22,23].…”