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Drag force, pressure distribution, and separation angle were measured on cylinders with diameters from 1/4 to 1-1/2 inch.Lift and drag forces acting on a NACA-0024 hydrofoil -model were also measured.The polymer additive was found to alter only those force coefficients which have a Reynolds-number transition region. Two distinct types of cylinder drag transition were observed:(1) At high concentrations, transition from sub-critical to a transcritical flow occurred at the same free-stream velocity independent of body diameter; and (2) at low concentrations and/or molecular weights, tripping from a sub-critical to a super-critical flow occurred at a well defined flow condition which was a function of the free-stream velocity body diameter, and turbulent pipe-flow friction reduction.In all cases, transition occurred earlier than that in the pure solvent. The polymer had a de-stabilizing effect on the boundary-layer flow. Lift and drag forces acting on a NACA-0024 hydrofoil -model were also measured.The polymer additive was found to alter only those force coefficients which have a Reynolds number transition region. Two distinct types of cylinder drag transition were observed:(1) At high concentrations, transition from sub-critical to a transcritical flow occurred at the same free stream velocity independent of body diameter; and (2) at low concentrations and/or molecular weights, tripping from a sub-critical to a super-critical flow occurred at a well defined flow condition which was a function of free stream velocity, body diameter and turbulent pipe-flow friction reduction.In all cases, transition occurred earlier than that in the pure solvent.The polymer had a de-stabilizing effect on the boundary layer flow.

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