A cross-correlation particle image velocimetry (PIV) method has been used to obtain detailed velocity measurements of flow over ripples in the Aberdeen Oscillatory Flow Tunnel. The new data is distinguished from previous work of this kind in that the measurements were made over full-scale, mobile ripples. A total of 14 velocity measurement experiments were carried out, covering a wide range of flow and mobility conditions and ripples with dimensions in the range 2.5 < η < 10 cm and 18.5 < λ < 55 cm. The paper presents example results from the measurements, illustrating the quality of the data and some important features of the flow behaviour. Attention is given to velocities near the ripple crest, velocities near the ripple surface, the time-averaged velocity field and the time- and horizontally-averaged velocity profiles.
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