Numerical investigation of the three-dimensional dynamic process of sabot discard

TLDR: In this article, the sabot discard behavior after projectile ejection from the muzzle is investigated at Mach number 4.0 and angle of attack of 0°, and 3D compressible equations implemented with a dynamic unstructured tetrahedral mesh are numerically solved with a commercial computational fluid dynamics (CFD) code (FLUENT 12.0).

Abstract: The sabot discard process of an armor-piercing, fin-stabilized discarding sabot (APFSDS) is crucial for the flight stability of the projectile. In this paper, the sabot discard behavior after projectile ejection from the muzzle is investigated at Mach number 4.0 and angle of attack of 0°. 3D compressible equations implemented with a dynamic unstructured tetrahedral mesh are numerically solved with a commercial computational fluid dynamics (CFD) code (FLUENT 12.0). Six-degrees-of-freedom (6DOF) rigid-body motion equations is solved with the CFD results through a user-defined function to update the sabot trajectory at every time step. A combination of springbased smoothing and local re-meshing is employed to regenerate the meshes around the sabot and describe its movement at each time step. Computational results show three different separation processes during the sabot discard process. Furthermore, the aerodynamic forces of APFSDS are calculated, and the trajectories of the three sabots are illustrated through the numerical solution of 6DOF equations. The results of the present study agree well with typical experimental results and provide detailed parameters that are important for analyzing the stability of the projectile. The present computations confirm that the numerical solution of the governing equations of aerodynamics and 6DOF rigid-body equations are a feasible method to study the sabot discard processes of APFSDS.