  The aerodynamics of a projectile launched from barrels of various devices is
quite complicated due to its interactions with the unsteady flow field around
it. A computational study using moving grid method is performed here to analyze
the effect of the projectile-shock wave interaction. Cylindrical and conical
projectiles have been employed to study such interactions and the fluid
dynamics of such flow fields. It is found that the overall effect of projectile
overtaking a blast wave on the unsteady aerodynamic characteristics of the
projectile is hardly affected by the projectile configurations. However, it is
noticed that the projectile configurations do affect the unsteady flow
structures and hence the drag coefficient for the conical projectile shows
considerable variation from that of the cylindrical projectile. The projectile
aerodynamic characteristics, when it interacts with the secondary shock wave,
are analyzed in detail. It is also observed that the change in the
characteristics of the secondary shock wave during the interaction is different
for different projectile configurations. Both inviscid and viscous simulations
were done to study the projectile aerodynamics. It is found that the effect of
the viscosity on the projectile aerodynamics is negligible but the viscosity
does affect the unsteady flow structures around the projectile.
