Geometry and migration characteristics of bedforms under waves and [An article from: Coastal Engineering]

This digital document is a journal article from Coastal Engineering, published by Elsevier in 2006. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.

Description:
In this paper the geometric and migration characteristics of sandwaves generated under the combined effect of waves and currents are described. Description and analysis of the flow structure along the centerline of developed sandwaves are also presented. The velocity distribution along the sandwave is used to explain, in part, the size and shape characteristics of the ripples superimposed upon the sandwaves (as discussed in the companion paper [Catano-Lopera, Y. and Garcia, M.H., in press. Geometry and migration characteristics of bedforms under waves and currents: Part 2, Ripples superimposed upon sandwaves. Coastal Engineering (doi:10.1016/j.coastaleng.2006.03.008).]). Variation in roughness height along the considered bed feature is also discussed for a particular experiment. Velocity measurements within the fluid were recorded with an Acoustic Doppler Velocimeter (ADV). An acoustic level sensor was employed to determine surface wave characteristics such as amplitude and period. 3D mapping of the bottom was done via a 32-composite-element array of sub-aquatic acoustic sensors (SeaTek-Multiple Transducer arrays). Bottom records were statistically analyzed to obtain height, length, migration rates of ripples and sandwaves and vertical growth rate of sandwaves. Experiments were conducted for the mobility factor and the Reynolds wave number within the ranges 10