| dc.description.abstract | Global increasing demand for aquatic foods, limitations of sheltered water locations, and ecological concerns have led a movement towards expanding marine finfish aquaculture to exposed waters in the open ocean. Despite the advantages of offshore fish farming, there are many challenges regarding the harsher environmental conditions in these locations, making it necessary to develop new concepts of fish farms to withstand these conditions. The purpose of this paper is to study a weather vanning module-based fish farm concept for operation in exposed waters. The concept consists of a turret-moored base-module and fish cage modules, where two rows of cage modules are connected to the moored base-module to form an “L” shaped fish farm. The module-based concept and easy connection systems between modules allow the fish farm to be easily arranged with different numbers of cages and only requires one mooring system for the whole fish farm. The hydrodynamic properties of the base-module have been obtained in the frequency-domain using a panel model. The grid-frame of the cage-modules has been modeled using slender cylindrical elements, where the hydrodynamic loads have been formulated using Morison’s equation. A simplified model of the nets is created with slender cylindrical elements using the screen model method to formulate equivalent hydrodynamic loads. The mooring lines are modeled as bar elements and the module connectors are modeled as beam elements. The coupled time-domain method was applied to perform sensitivity studies on the number of cage-modules in the fish farm, wave conditions, and current velocities. The responses investigated in detail include the global motion responses of the base-module, tension in the mooring lines, and axial forces in the connectors. | |
