Design and arrangement technology of artificial habitat using old vessel

Abstract

To recycle old fishing vessel as an artificial habitat, design technology is established through physical experiment and numerical simulation. Numerical simulation based on finite volume method with standard κ-ε model and hydraulic experiment using flow visualization scheme are applied to determine sheltered area and reasonable interval between vessel habitats. Reattachment length, as an index of the area, is ranged from 5 to 10 times of vessel height according to Reynolds number. It is necessary of the interval more than 4 times of the length to maximize total area. As results of hydrodynamic experiment, drag coefficient from 1.5 to 2.0 and lift coefficient from 0.3 to 0.8 according to Reynolds number in current field, inertia coefficient of 0.5 in wave field can be applied to estimate demanded weight. Additional measures to enhance fish aggregation are discussed on opening holes with regard to ecological habit of target fish as well as attaching membranes on the hull.