Hydrodynamic effect of different biofouling types on aquaculture netting

Biofouling on netting is an important problem, which can increase hydrodynamics and reduce water exchange across the netting. In this study, drag effect of netting panels with artificial hard and flexible fouling was investigated by physical model tests. The results showed that fouling can cause a rapid increase in netting drag, and that the drag amplification factor of a netting caused by severe hard fouling can be up to 30 times higher than that of a clean netting. With increasing fouling, the drag coefficients for artificial hard fouling can up to 54% higher than those flexible fouling. The formulae proposed to predict the drag coefficients of netting panels with severe hard fouling, can provide a conservative drag coefficient for netting cage design to evaluate the cage safety.

Automated summary

Biofouling on netting is a significant problem that impacts hydrodynamics and water exchange. Physical model tests were conducted to investigate the drag effect of netting panels with artificial hard and flexible fouling. The results indicated that fouling can rapidly increase netting drag, with severe hard fouling causing a drag amplification factor up to 30 times higher than clean netting. The drag coefficients for artificial hard fouling were found to be up to 54% higher than those for flexible fouling. The proposed formulas for predicting drag coefficients can be used to evaluate cage safety in netting cage design.