Abstract

The determination of mooring tension on a prototype cage for salmon production on exposed areas in southern Chile is obtained using experiments at laboratory scale, numerical simulations as well as on site measurements using a submersible load cell. The 40m diameter prototype cage used in this study is constructed out of HDPE pipe and has a ballast tank attached to the bottom to control the operational depth in case of high waves. The cage uses a copper nickel alloy net cancelling the need for a predatory net as in traditional systems. First, drag coefficients for the net were obtained at the Wave/Towing tank at Universidad Austral de Chile (UACh), plus the characterization of dynamic response and deformation of two cage models. These results were used as input for numerical simulations of the cage using the commercial software AquaSim. The last stage of the campaign was the measurement of tension on the prototype cage, using a load cell on a mooring line along with measurements of tides, wind, waves, and currents. The results are the base for a more complex analysis, since the net, due to its geometry, stiffness and wet weight, has a particular behavior when compared to traditional fiber-based nets.