Acquacoltura e Pesca Pubblicazione scientifica Numerical And Experimental Study of Submerged Flexible Nets: Applications to Fish Farms FILONE TECNOLOGICO TEMA produzione e cattura produzione e raccolta RIASSUNTO Our aim is to model the dynamic behaviour of submerged flexible nets in any relative current. Due to both the discontinuous and highly flexible nature of the nets and the complexity of the flow through the mesh, this study involves both structure mechanics and fluid mechanics. We describe a numerical method to resolve this complex fluid - structure coupling problem. We have applied this method to fish farming cages with flexible nets. Measuring the hydrodynamic forces applied to net panels allows to validate the Landweber- Richtmeyer model. Finally, we compare the shapes of cage models obtained numerically and experimentally. INTRODUCTION Aquaculture may allow to solve a number of problems in connection with the difficulties inherent in fisheries and with the excessive exploitation of the natural ressources. Extrapolation of trends (Beveridge 1996) suggests that at the end of the first quarter of the next century, farmed fish production will have outstripped capture fisheries production and will be the most important means of providing fish for food. That is the reason for the development of aquaculture with net cages in the coastal zone. The evolution of fish farming has lead the equipment manufacturers to offer new farming structures adapted to the different species. The floating cage we are going to study (figure 1) represents the greater majority of fish farming equipment used in the sea. It is held in place at the surface by a buoyant support which is moored to the seabed. We provide a numerical method to determine the shape and the tensile forces applied to a submerged floating cage situated in a uniform transverse current. But nets are both discontinuous and anisotropic structures which can be considered as infinitely flexible. The permeability of the meshes allows flow of water through the net to vary greatly. DATA Data di pubblicazione: 14/06/2013 AUTORI LE BRIS F MARICHAL D ENTE DI AFFERENZA ECOLE CENTRALE DE NANTES RIVISTA The Ninth International Offshore and Polar Engineering Conference, 30 May-4 June, Brest, France