SHEETFLOW SEDIMENT TRANSPORT UNDER ASYMMETRIC WAVES AND STRONG CURRENTS

Le Phuong Dong, Shinji Sato

Abstract


Experiments have been conducted to investigate the sheetflow sediment transport of uniform sand under asymmetric oscillatory flows in combination with relatively strong opposite currents. Two kinds of nearshore waves were performed, namely, velocity asymmetric waves and acceleration asymmetric waves. Image analysis technique is utilized to study major influences of wave shapes and current through observing the instantaneous sheetflow layer thickness. Maximum sheetflow layer thickness was formulated and incorporated to an enhanced Watanabe and Sato’s formulation. The new conceptual model is examined its validity for a wide range of experimental conditions

Keywords


sheetflow; oscillatory flow; sediment transport; net transport rates formula; asymmetric waves; currents

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