This paper describes experiments on smooth body adverse pressure gradient (APG) turbulent boundary layer flow separation for the purpose of CFD validation and model development. The experimental geometry is designed to provide initial canonical turbulent boundary layer growth under nominally zero pressure gradient conditions prior to encountering a large, smooth, two-dimensional convex ramp geometry onto which a streamwise APG that is fully adjustable is imposed. Experiments encompassing both large-and small-scale smooth body flow separation as well as attached APG turbulent boundary layer development are realized on the same ramp geometry. The reported experiments are performed at M_∞ = 0.2 which corresponds to Re_θ ≈ 11,000 at the onset of the APG. Sample results are presented for the small-scale separation case and these include the evolution of both the mean flow and turbulent stresses at multiple spanwise locations on the ramp. Application of embedded shear layer scaling is shown to fully collapse the inflectional mean velocity profiles at all streamwise and spanwise locations on the ramp. When similar scaling is applied to the turbulent stresses, evidence of the effect of ramp surface curvature emerges. Due to the rapid transition from initially convex to concave curvature, it is demonstrated that the Reynolds stresses are effectively frozen.
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