Wind tunnel verification of base-bleed effects on aerodynamic characteristics of an axi-symmetric projectile

Experimental verification of base-bleed effects on aerodynamic characteristics for the supersonic flight stages was requested during the development of an axi-symmetric projectile. The experimental setup for testing base-bleed configurations of the projectile was designed, built and tested in the T-38 trisonic blowdown wind tunnel of the Military Technical Institute (VTI), Belgrade. Gas-generator was formed from a simple chamber with a single manifold pneumatically connected to a high-pressure air supply. Wind tunnel tests comprised measurement of aerodynamic forces and moments of the projectile with active base-bleed. Flow visualization was performed using the Schlieren method. It was of interest to verify the base drag reduction in the wind tunnel tests and to compare it with numerical predictions. In addition, the experience gained during these tests has been found to be helpful in the design of the future similar wind tunnel setups