NUMERICAL SIMULATION OF WAKE EFFECT IN NETS UNDER STEADY CURRENT Conference Paper uri icon

abstract

  • 2015 by ASME. To accurately describe the dynamic response of aquaculture cages exposed to current loading, it is necessary to consider the reduction of fluid velocity due to the presence of the net. In this study, three wake models, originally developed for riser interaction, are applied to a cylindrical net to evaluate drag force, volume and projected area reduction when exposed to steady currents. The results are compared to available experimental data to validate the methodology and evaluate the wake models' accuracy. The net has been modeled using the commercial software OrcaFlex. This tool is a fully nonlinear finite element software, capable to compute forces and displacements of the net when exposed to current and wave loading. Calculations were performed under a series of current speed and three ballast weight conditions. The effect of the number of elements used to describe the net is analyzed as well. Results without including wake effect show good agreement for drag force up to moderate current speeds. Nevertheless a significant improvement on drag force results was achieved when wake effect is included. Yet, at high current speed and heavier ballast, drag force is over predicted. Minor differences were found when different wake models are used. In addition, it is concluded that an increase on the number of elements shows no significant influence on drag force results. On the other hand, calculations for volume and projected area reduction get closer to experimental values. The findings confirm the relevance of wake effect on nets and serve as validation of the present numerical procedure.

published proceedings

  • PROCEEDINGS OF THE ASME 34TH INTERNATIONAL CONFERENCE ON OCEAN, OFFSHORE AND ARCTIC ENGINEERING, 2015, VOL 6

author list (cited authors)

  • Cifuentes, C., Kim, M. H., & ASME.

complete list of authors

  • Cifuentes, Cristian||Kim, MH

publication date

  • January 2015