Aquatic vegetation in rivers and coastal regions controls the flow structure in terms of mean velocity and turbulence. The vegetation in the flow affects the transportation of nutrients, microbes, dissolved oxygen, sediment, and contaminants; therefore, the flow characteristics of different types of vegetation layers should be examined in order to understand the effects of vegetation on the flow structure. In this paper, the effect of the submergence ratio and SVF (Solid Volume of Fraction) of a vegetation patch, which was present across half of the channel in a spanwise direction, on the flow structure at the wake region was examined. For this purpose, different submergence ratios with different SVFs were considered in the experiments, and velocity measurements were performed in the wake region of the vegetation layer with an Acoustic Doppler Velocimeter (ADV). According to the results, the effect of different vegetation heights and SVFs on the velocity distribution was obtained. Moreover, inflectional velocity distribution over the cross-section in the wake region of the vegetation layer was obtained, and it was concluded that jet flow occurred in the non-vegetated half of the channel due to the vegetation layer.

2 3The problem of propeller jet-induced erosion has significantly risen during the past three decades due to an increase in the manoeuvrability of ships. Therefore, propeller-induced scours need to be considered in the design of quay structures. In this study, the effect of slope angle on propeller jet erosion was examined. Three different slope angles of m 5 2?5, 2?0 and 1?5 were considered. Additionally, three different cases were considered, including an armoured layer with and without a toe apron and pile on an armoured layer with a toe apron. Flow velocity and scour measurements were performed in the experiments. For each slope angle, armour layer damage on the slope was defined by use of a damage level parameter. In addition, critical densimetric Froude numbers (Fr d,cr ) were defined for the start of damage at different slope angles.

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