Inner Barrel Weapon Barrel Bore And Flow Field Numerical Simulation Of Heat Conduction

The problem of gun erosion is getting more and more serous because of increasing high chamber pressure, high muzzle velocity and high firing rate. So, tube life is faced to enormous challenges. To understand the essence of gun erosion more clearly and provide a theoretical basis for the design of structural or tube life, etc, the numerical simulation of propellant gas and heat transfer of gun barrel during firing in a7.62mm submachine gun was conducted. Additionally, the temperature history of the out surface of gun barrel was measured.First, according to two-phase flow theory of internal ballistics and based on computational fluid dynamics, the mathematical model of the core flow of propellant gas was established. And the discrete equations were obtained by MacCormack scheme.Secondly, Prandtl turbulent boundary layer equations were deduced based on the analysis of N-S equations, then a finite difference scheme was derived based on Taylor expansion.Thirdly, a two-dimensional heat conduction mathematical model of gun barrel was established and a finite difference scheme was derived using ADI (Alternating Difference Implicit) scheme.Fourthly, gas flow, boundary layer and heat transfer of gun barrel during single shot and bursts were calculated numerically with FORTRAN program, and the internal ballistic parameters of propellant gas and temperature distribution of gun barrel were obtained.Fifthly, the experiment was conducted to measure the temperature of out surface of gun tube with thermal imager. The numerical results were consistent with the experimental results, which proved the reliability of the mathematical model and numerical methods used in this paper.The research results have great importance for the further studies of gun barrel erosion mechanism.