Journals Proceedings

Abstract

The characteristics of velocity fields of the external and boundary layer flows during run-up motion of a non-breaking solitary wave propagating over a 1:3 sloping beach are explored experimentally. Flow visualization technique (FVT) of particle trajectory photography and high-speed particle image velocimetry (HSPIV) were employed to qualitatively observe and quantitatively measure the macro-viewed external and micro-viewed boundary layer flow fields. The experiments were conducted in wave flume equipped with a wave maker being triggered by a precise servo-motor. The incident wave-height to water-depth ratios, H0/h0, is equal to 0.363. The slope of the sloping beach model is fixed at 1:3. Profoundly distinct characteristics of flow fields around the flow demarcation curves, as observed respectively from the macro-viewed external flow and the micro-viewed boundary layer flow, are first interpreted, together with elucidation of the flow reversal exhibiting wall-jet-like feature. A promising similarity profile of the flow reversal underlying the flow demarcation curve is proposed by selecting the characteristic length and velocity scales in the boundary layer flow.