Study on the computing methods of mixed layer depth and gradation based on sand wave motion

M Zhang, Y Yang, H Zhang
2017 Bulgarian Chemical Communications, Special Edition H   unpublished
As for non-uniform sand mathematical models, the determination of mixed layer depth and gradation is of extremely important significance and will directly decide the reliability and accuracy of corresponding computing results. On the basis of sufficient indoor and outdoor data, the relation curve between relative wave height and relative velocity is represented, with curve parameters being matched; besides, based on the physical meanings of mixed layer depth and its relation with sand wave
more » ... t, the sand wave motion-based computing method of mixed layer depth is derived out. Starting from the concept of mixed layer, it is assumed that the original bed material gradation will be uniform along depth, the porosity remains unchanged before and after scouring and silting, blending layer depth is a constant in the computing period, scoured sediment will be substituted equivalently by original bed materials below blending layer's lower boundary, deposited sediment will lead to equivalent ascending and descending of blending layer's upper and lower boundaries, the mixing will be uniform in the process, and the estimation methods of the sand wave bed's mixed layer under three models are derived out and obtained, including the pure deposition model, the pure scouring model and the coarse-deposition fine-scouring model.