Computational fluid dynamics (CFD) modelling of aerodynamic coefficients of projectiles moving at subsonic and supersonic speed

Aerodynamic coefficients of drag, lift and overturning moment for a small-calibre projectile are calculated using computational fluid dynamic (CFD) modelling applying the Fluent hydrocode. 250 computational cores were used in a cluster of 1600. The aerodynamic coefficients are well approximated using a third order polynomial in yaw in the subsonic and supersonic regions. A comparison is made with data from the literature. CFD results of drag coefficient agree well with results based on radar measurements.

Generally, CFD seems to provide a basis for significant improvement in projectile accuracy across all calibers of ammunition. It can be argued that this can have large importance for future development of ammunition. Work beyond this report is in progress and has been performed for 120 mm tank ammunition with success theoretically and practically.

Section 2 considers the general theory of projectiles. Section 3 shows analytical theory of aerodynamic coefficients. Section 4 presents results, while Section 5 concludes with discussion.