Computational Investigation of Base Drag Reduction for a Projectile at Different Flight Regimes

Abstract

A computational investigation for the 155mm artillery shell was conducted for the purpose of reducing the base drag. Three case studies were conducted to investigate the properties of the flow field around the shell for the flight at different Mach numbers at zero angle of attack. The three cases were: a shell with boattail, a shell with base cavity and a shell with base bleed. Also, combinations of these three cases were investigated. The higher drag reduction was demonstrated when using a combination of the three effects. For this latter case it was possible to realize a drag coefficient reduction of ~60% at subsonic regime and ~20-30% .at transonic and supersonic regimes. Based on the present methodology, a design optimization for minimum drag can be applied on similar flying bodies.