Abstract:
The feasibility of sustainable aquaculture in nearshore waters can be challenging due to the rise in stakeholder conflicts, coastal environmental pollution, and spatial constraints. While offshore aquaculture farms have evolved as a potential solution, currently, these systems require comprehensive engineering analysis-based design to withstand extreme weather conditions such as storms and strong currents. In this study, historical wave and current data from New England offshore waters were collected, analyzed, and sta- tistically modeled. The information was used as input for the numerical simulations of a continuous mussel longline system design at different mussel growth stages using Hydro-FE to predict the dynamic response of the longline at several wave/current/water depth configurations. Hydro-FE [1] is an advanced version of the finite element software, Aqua-FE [2,3,4] developed at the University of New Hampshire to analyze submerged flexible structures. The components of the mussel longline are modeled using truss and beam elements and the input parameters, such as the normal and tangential drag coeffi- cients. The coefficients are estimated separately via computational fluid dynamics (CFD) simulations in OpenFOAM. The Hydro-FE simulation results are analyzed based on the mooring line stress, anchor forces, and displacement time series to find the possible anchor failure, rope breakage, line entanglement, and mussel falloff in different configurations. General guidelines for a typical offshore mussel longline system are provided based on the quantitative analysis.
References
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