Time resolved particle image velocimetry was used to investigatenew aspects of the flow field associated with a vortex ring/moving wall interaction. These physical simulations representaspects of the instantaneous flow field interactions known to existin turbulent wall-bounded flows. To allow for an explicitstudy of these interactions and avoid background turbulence,unsteady, laminar, vortex ring experiments were conducted withreproducible initial conditions. For the case when the vorticityin the bottom core of the ring and shear layer have oppositesign, the passage of the vortex ring above the wall results in alifting of the near wall fluid. This gives rise to the formation ofa primary hairpin vortex with the same sign vorticity as the topcore of the vortex ring. The results obtained indicate that thering rebounds from the wall for these interactions at increasingangles for increasing incident angles. Furthermore, the hairpinlift up occurs over shorter time scales when the incidence angleof the vortex ring was increased. The results provide furtherinsight into how vortical structures interact and the associatedmomentum transport mechanisms relevant to turbulent flows.
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