Numerical models and intercomparisons of beach profile evolution

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• 作者：Jie ; Zheng ; Dean ; Robert G.
• 关键词：Dune erosion ; Numerical models ; Storm effects ; Beach erosion ; Erosion prediction
• 刊名：Coastal Engineering
• 出版年：1997
• 出版时间：May, 1997
• 年：1997
• 卷：30
• 期：3-4
• 页码：169-201
• 全文大小：1.40 M

文摘

A modified non-linear cross-shore sediment transport relationship is developed based on equilibrium beach profile concepts and scaling relationships. This non-linear relationship provides a reasonable explanation for the significantly different time scales of beach evolution evident in various laboratory experiments. The proposed non-linear model called “CROSS” is calibrated and compared with the commonly employed linear transport relationship using laboratory data. A total of seven large scale wave tank experiments from three different facilities are examined. The results demonstrate that the non-linear transport model provides better overall predictions than the linear transport equations. The CROSS model and three other commonly used models are applied to predict beach erosion at Ocean City, Maryland during the November 11, 1991 and January 4, 1992 storms. Seven survey lines are available for comparison with the numerical simulations. Overall, CROSS, EDUNE and SBEACH (version 3.0) provide reasonable predictions for both dune erosion and the entire profiles. The sensitivity of CROSS to the transport coefficient, active water depth, storm surge levels and the storm wave heights are examined for the storm erosion at Ocean City. It appears that CROSS is quite insensitive to the transport coefficient. The subaqueous part of a profile is quite sensitive to the wave height and the subaerial part is less affected. The CROSS model provides better predictions with the ratio of active water depth to incoming wave height of 1 than with the ratio of 1.28, and the 20 % increased storm surge yields a better simulation.