Abstract
In this study, a physics-based morphology model is developed and to test the feasibility of the morphology model proposed in this study as the platform for the optimal design of the beach nourishment project, the beach restoration process by the infra-gravity waves underlying the swells in a mild sea is numerically simulated. As a hydrodynamic module, the IHFOAM wave toolbox having its roots in the OpenFoam is used. Speaking of the morphology model, a transport equation for suspended load and the Exner type equation constitute the morphology model. In doing so, the probability theory first introduced by Einstein and the physical model test by Bagnold are used as the constituent sub-model of the morphology model. Numerical results show that among many flow features that are indispensable in forming sand bars over the flat bottom and swash zone, the partially skewed and asymmetric bottom shearing stresses, a shoreward Stokes drift near the free surface, boundary layer streaming near the seabed, and undertow toward the offshore were successfully simulated using the morphology model proposed in this study. It was also shown that plunging type breaker occurring at the final stage of the shoaling process, and its accompanying second breaker, sediment entrainment at the seabed, and the redistribution of suspended load by the down rush of preceding waves were successfully reproduced in the numerical simulation, and agreements with our experience in the field were very encouraging. In particular, the sand bar formation process over the flat bottom and backshore were successfully reproduced in the numerical simulation, which has been regarded as a challenging task.
Highlights
Over the last few years, beaches along the east coast of South Korea have been suffering from severe erosion since the quasi-equilibrium water environment that they once enjoyed has been damaged by poorly executed development [1,2]
In the light of the discussions mentioned above, it can be perceived that numerical duplication of sand waves or ripples formed on the flat bottom, which is regarded as the benchmark test of a physics-based 3D morphology model to work as the platform for the optimal design of a beach nourishment project, would be plausible utilizing the RANS and physics-based morphology model having the probability theory first introduced by Einstein [15] and the physical model test by Bagnold [16] as the constituent sub-model
In order to test the feasibility of the morphology model presented in this study as the platform for the optimal design of the beach nourishment project, the beach restoration process by the infra-gravity waves underlying the swells in a mild sea was numerically simulated
Summary
Over the last few years, beaches along the east coast of South Korea have been suffering from severe erosion since the quasi-equilibrium water environment that they once enjoyed has been damaged by poorly executed development [1,2]. In the light of the discussions mentioned above, it can be perceived that numerical duplication of sand waves or ripples formed on the flat bottom, which is regarded as the benchmark test of a physics-based 3D morphology model to work as the platform for the optimal design of a beach nourishment project, would be plausible utilizing the RANS and physics-based morphology model having the probability theory first introduced by Einstein [15] and the physical model test by Bagnold [16] as the constituent sub-model In this rationale, this study intends to test the hypothesis mentioned above, using the numerically simulated beach profile exposed to waves using the revised physics-based morphology model by Cho [13,14] that consists of the phase-resolving RANS coupled with a transport equation for suspended load, and morphology equation of Exner type.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
