Subsonic Axisymmetric Near-Wake Studies

The turbulent near-wake of a cylindrical blunt-based body aligned with a uniform freestream was experimentally investigated. Tests were conducted over the entire subsonic Mach number range in a wind tunnel utilizing an upstream model support system. Results indicate that the separation process influences the flow approaching the blunt base for at least 3 model diameters. The base pressure coefficient is constant for Mach numbers less than 0.8, but drops rapidly at near-sonic speeds. The size of the near-wake increases with Mach number. A similarity expression for the near-wake centerline velocity distribution is developed.