Computational Analysis of Base Drag Reduction for a Subsonic Missile Projectile at Different Flow Velocity Conditions.

Base drag is arising from flow separation at blunt base of a body. It can be a sizeable fraction of total drag in context of projectiles, missiles and after bodies of fighter aircrafts. The base drag is the major contribution of total drag for low speed regimes. Flight tests have shown that the base drag may account for up to 50% of total drag. In this paper an experimental work on a simple semi-circular flight vehicle body of length 500mm and diameter 50mm was conducted for the purpose of investigating base drag. The base drags for three configurations are calculated and the results are compared with CFD data. The three configurations used for testing are flat base configuration, closed nozzle configuration and boat tail configuration. The evaluations of base drag for the flow velocities of 20m/s, 35m/s and 50m/s at angles of attack such as -2 °, 0 ° and 2 ° are experimented and compared. [ABSTRACT FROM AUTHOR]