Two-component laser Doppler velocimetry was used to obtain detailed mean velocity and turbulence measure- ments in the near wake of a cylindrical after body with base bleed in a Mach 2.5 flow. The bleed flow provides at least some of the fluid required for shear layer entrainment and shields the base annulus from the outer shear layer and the primary recirculation region, leading to an increase in base pressure. There is an overall reduction in turbulence levels throughout the base bleed flowfields relative to the near-wake flowfields of blunt-based and boattailed afterbodies. With increasing bleed, the formation of a strong bleed jet shear layer and secondary recir- culation region near the base annulus offsets the benefits of base bleed, leading to a drop in the base pressure.
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