Analytical and numerical studies of gas discharge out of gun barrel tube

Abstract

Abstract This paper investigates the characteristics of the discharge of gases out of gun barrel tube. The paper gives an insight into the physical principles that govern gas discharge through the presentation of analytical and two different numerical approaches. The analytical model is based on the well-known Bravin’s model, whereas the numerical approaches involve single- and two-phase flow numerical simulations conducted by utilities of Computational Fluid Dynamics (CFD). The differences between analytical and numerical results are analysed, from which the numerical approach is found to be capable of capturing the interacting phenomena due to the discharge of hot and high-pressure gases. The visualisation of flow parameters manifests the complex dynamics evoked by flow patterns and the formation of Mach disc and shock waves. It is found that the analytical Bravin’s model underestimates the pressure decay inside the barrel due to gas discharge compared to both the single- and two-phase flow numerical approaches.