Large-eddy simulations of ship channel and shallow bay interactions under wind and wave forcings

Many embayments around Gulf of Mexico, e.g., Corpus Christi Bay and Galveston Bay, feature a shallow barrier-island type bay with a deep artificial ship channel. In these embayment systems, the river and tidal flows are weak and the mixing and transport are dominated by the effects of wind- and wave-driven flows. The interaction between wind and waves causes the generation of Langmuir turbulence (i.e., the combination of large coherent Langmuir circulations and small-scale turbulence), which can induce considerable transport of salinity, nutrient, and sediment between the bay and the ship channel. Langmuir circulations also exhibit noticeable change of intensity as they travel over the ship channel region, which further complicates the channel–bay interaction. In this work, the dynamics of Langmuir turbulence in the channel–bay coupled system is modeled using large-eddy simulation (LES). A suite of LES cases is performed to cover different wind and wave conditions, based on which the material exchanges between the shallow bay and the deep shape channel are quantified.