Pan, Y.; Yin, S.; Chen, Y.; Yang, Y.; Xu, Z., and Xu, C., 2019. A practical method to scale the sedimentary parameters in a lightweight coastal mobile bed model. Journal of Coastal Research, 35(6), 1351–1357. Coconut Creek (Florida), ISSN 0749-0208.
The coastal mobile bed model (CMBM) is an important approach to understand coastal sedimentary processes. The scaling of sedimentary parameters in a reduced-scale CMBM is one of the key procedures ensuring the reliability of the model, and the scaling relationships should be derived according to the similarity of dominant sedimentary process, with some less important similarity relationships relaxed. For a CMBM of which the processes of mobilization and fall of sediment are in transitional conditions, the scaling of sedimentary parameters is especially difficult because no mechanism dominates and the relationships between parameters are complicated. This paper proposes a local curve-fitting (LCF) method to avoid complicated relationships in deriving scaling relationships by fitting the complicated expressions with a simple relationship in the study range so that the scaling relationships can satisfy corresponding similarity criterion. The LCF method is introduced via the scaling of a reduced-scale profile model of the evolution of a submerged berm under the effects of small waves. The scaling relationships are derived according to the similarities of sediment mobilization, similarities of the fall of sediment, and Froude criterion. A mobile bed model was created based on the calculated of the LCF method, and the model results show the same evolution trend with field data, which proves the reasonability and validity of the LCF method. The LCF method provides a practical method to facilitate the deriving of scaling relationships of a CMBM of which the processes of mobilization and fall of sediment are in transitional conditions. It also provides a reference for other reduced-scale laboratory tests with complicated relationships between parameters but with limited study ranges.