| dc.description.abstract | Drag tests on aquaculture net panels were carried out in the towing tank Lilletanken (NTNU) for fifteen current velocities. The data were post-treated and discussed in order to characterize the dependency of the drag forces on several parameters, as the solidity ratio, the Reynold number, or the nets' material and size.\\
The behaviour of the turbulent flows around, and in the wake of the net panels has then been described. \\
Several experiments were also achieved in model-scale for wave conditions. The resulting loads were analyzed, and the influence of the wave periods and steepness on the loads were then investigated. The study has been extended to the force amplitude harmonics, significant for high steepness. \\
In parallel, CFD models were created in the open source software OpenFoam. They have been defined from the dimensions and properties of the experimental installation in order to produce comparable results. A convergence study was achieved to mesh 2D top and side views of the system.\\
The twines of the nets were too small to be meshed, and were modeled thanks to a pressure drop added in the Navier-Stokes equations. \\
The results revealed large differences between the numerical and experimental loads for high solidity ratios. The uncertainties linked to the experimental set-up have been discussed, focusing on the water elevation on the nets during the experiments, or the speed-up caused by the frames supporting the nets. | |
