Abstract: To investigate the mechanism of engraving process and the rule of initial motion of projectile during lauching process, the engraving process of rotating band of large-caliber howitzer is simulated. The gas pressure distribution of propellant in the tapered chamber is taken into consideration to get the interior ballistic equation during engraving process, and the solution of the equation is taken as the boundary condition of coupled thermo-mechanical analysis of engraving process. Meanwhile, the friction between the rotating band and the barrel is modeled using modified Coulomb model in which the temperature at the interface is taken into consideration. Uncoupled internal ballistic engraving process and adiabatic engraving process are calculated to verify the necessity of the coupled analysis. The resistance, projectile velocity, propellant gas pressure and projectile attitude are got by considering the changes in clearance between projectile and barrel, initial velocity and initial projectile attitude. The calculated results show that the clearance between projectile and barrel plays an important role in determining the resistance and projectile velocity, and the initial projectile attitude has a great effect on the projectile attitude in the process of engraving.

Key words: ordnance science and technology, coupled thermo-mechanical, engraving resistance, projectile attitude