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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. [ABSTRACT FROM AUTHOR]

ABSTRACT Xu, C.Y.; Chen, Y.P., and Yu, L.L., 2018. Numerical Studying on The Sedimentary Processes at A Mudflat Near Yangtze River. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 1201–1205. Coconut Creek (Florida), ISSN 0749-0208. A two-phase model for studying the sedimentation processes is presented. The simple flocculation model is incorporated in the two-phase model to take account the flocculation effects on the settling velocity and thus the distribution of suspended sediment concentration. The model is applied to study the sedimentation processes at a mudflat and the suspended sediment concentration is presented and compared with measured data. The results show that it is important to include the flocculation effects in predicting the vertical profile of sediment concentration. [ABSTRACT FROM AUTHOR]

ABSTRACT Zhou, C.Y.; Xu, C.Y.; Zhang, J.S.; Fu, X.Y., and Yin, Y., 2018. Coastal hazards caused by different extreme storms in the Bohai Sea, China. In: Shim, J.-S.; Chun, I., and Lim, H.S. (eds.), Proceedings from the International Coastal Symposium (ICS) 2018 (Busan, Republic of Korea). Journal of Coastal Research, Special Issue No. 85, pp. 816–820. Coconut Creek (Florida), ISSN 0749-0208. The Bohai Sea, a semi-enclosed epicontinental sea, suffers different storms frequently, mainly tropical cyclones in summer/autumn and cold waves in winter/spring. The extreme storms can cause severe coastal hazards such as flooding, coastal structures and ocean platforms failures. A numerical model is set up for the Bohai Sea using MIKE21 with coupled hydrodynamic and wave modules. Observed data of water levels, velocities and wave are used to make model calibration. Based on this model, three typical tropical cyclones and cold waves are simulated. Then the major characteristics of summer tropical cyclones and winter cold waves are discussed. Affected by the tropical cyclone, the water levels of Laizhou Bay and Bohai Bay increase and that of Liaodong Bay decreases. Influenced by the cold wave coupled with an extratropical cyclone, the water levels of Laizhou Bay and Bohai Bay decrease firstly and then increase, which is contrary to the variation trend of water level at Liaodong Bay. Under the single cold wave weather, the water level increases at Laizhou Bay, decreases at Liaodong Bay, and firstly increases then decreases at Bohai Bay. The maximum of surge level caused by cold wave coupled with extratropical cyclone is smaller than that induced by tropical cyclone and single cold wave weather. [ABSTRACT FROM AUTHOR]

Xu, C. and Dong, P., 2017. A dynamic model for coastal mud flocs with distributed fractal dimension. Suspended sediments entrained from muddy estuarine and coastal areas usually contain a large amount of mud flocs of various sizes and densities. The size and settling velocity of these mud flocs are unsteady and may vary over a large range. In most theoretical descriptions the mud flocs are treated as self-similar fractal entities with the fractal dimension being considered as either a constant or a simple function of the mean floc size. This deterministic description of fractal dimension has recently been found to be inadequate as for a given size class; fractal dimension of the mud flocs is not a single value but is distributed over a certain range. To address this problem this paper proposes a new flocculation model for the temporal evolution of floc size by considering the fractal dimensions for a given floc size class D to be normally distributed and validates the model with available experimental data. The proposed model is found to perform better in predicting the temporal evolution of floc size than that based on a single fixed floc-size-dependent fractal dimension, especially under high shear conditions and with large equilibrium floc size. [ABSTRACT FROM AUTHOR]