CFD Simulation of Propellant Gas Flow Motion in Gas-Operated Systems

In this research, computational fluid dynamics (CFD) is used to study the discharge flow of the propellant gases via gas vent of automatic weapons by using the propellant gases taken from ports in the barrel bore to drive the automatic system. A numerical model of gas flow motion in the gas cylinder is based on thermodynamics theory which was investigated, defined, and built into the CFD tool of the ANSYS FLUENT software. The approximate solutions are obtained by using k-omega turbulence model. Results show the velocity field, the pressure field, and the temperature field of the propellant gases flow in the gas cylinder and the cylinder walls. The comparisons between results obtained by the analytical model and the numerical simulation have been performed and good agreements were observed. These thermodynamic simulation results lay foundation to solve the problem concerning research into the gas-operated device's structural parameter design and to determine the location of high-pressure and temperature zones of gas block while firing, leading to the choice of materials and optimal design for gas-operated device details.