Sammendrag
The effects of juvenile Atlantic salmon (Salmo salar) on flow and turbulence in a circular tank were investigated. Three fish sizes were studied
(37.5 g, 82.5 g and 218 g) with between 268,050 and 318,000 fish in a 15 m diameter by 4 m deep tank (mean stocking densities of 15.3 kg m–3,
35.6 kg m–3, and 79.4 kg m–3). Flow in the enclosed tank was driven by the inflow from the water supply system and a degassing system. Velocities
were measured using acoustic Doppler velocimetry with and without fish present. Dissolved oxygen was also measured, and the turbulent transport
of dissolved oxygen calculated from eddy correlation. The average water velocity was reduced by 15% at low and medium stocking densities, and
57% at high stocking density. Turbulent kinetic energy, turbulence intensity, and turbulence dissipation rates were higher with fish than without. Fish
altered the distributions of mean velocity, turbulence and oxygen, and increased the turbulent transport of oxygen. Vertical distributions of turbulence
were consistent with echo-sounder derived fish distributions.
(37.5 g, 82.5 g and 218 g) with between 268,050 and 318,000 fish in a 15 m diameter by 4 m deep tank (mean stocking densities of 15.3 kg m–3,
35.6 kg m–3, and 79.4 kg m–3). Flow in the enclosed tank was driven by the inflow from the water supply system and a degassing system. Velocities
were measured using acoustic Doppler velocimetry with and without fish present. Dissolved oxygen was also measured, and the turbulent transport
of dissolved oxygen calculated from eddy correlation. The average water velocity was reduced by 15% at low and medium stocking densities, and
57% at high stocking density. Turbulent kinetic energy, turbulence intensity, and turbulence dissipation rates were higher with fish than without. Fish
altered the distributions of mean velocity, turbulence and oxygen, and increased the turbulent transport of oxygen. Vertical distributions of turbulence
were consistent with echo-sounder derived fish distributions.