The modes of Sediment Transport under pulsatile Motion

摘要

Existing experimental data of sediment movmeent due to waves and current coexistent motion, or pulsatile motion, are collected to investigate hte modes of sediment transport. the data set analyzed in this study covers very wide range of experimnetla condition, i.e., experimental facility, angle of wavecurrent interaction, size of bed material and relative magnitude of waves and current. It is found that there are three major types of movement: no motion, rippled bed and sheet flow conditions, being similar to those induced by purely oscillatory motion. furthermore, employing a dimensionless parameter in terms of bottom shear velocity, which can be evaluated by uisng one of the authors' friction coefficient formula, along with a dimensionless grain diameter, a regime diagram for sediment movement can be obtained. It shows remarkable resemblance to a diagram for pure wave motion in previous investigations.