Simulation of the Motion of a School Of Fish in a Uniformly Stratified Fluid

The field of disturbances from a school of commercial fish moving at a constant depth is investigated. The fluid is considered to be ideal and uniformly stratified. A school of fish is modeled by a group of identical point mass sources. The sources move horizontally and rectilinearly at the same speed or along the same sinusoidal trajectories with a random phase shift. A 90-degree rotation of the flock is also simulated. It is found that the result of solving the problem differs significantly from the known asymptotics near the flock, as well as in the case of rapid changes in the speed of motion of the flock, while the motion of fish along sinusoidal trajectories has little effect on the character of disturbances compared to rectilinear motion. The effect of the change in the distance between the fishes on the velocity fields of the fluid is studied. A significant influence of the distance between fish in a flock on the disturbance pattern is found at distances of the order of several flock sizes, whereas in the far zone, the disturbance pattern of the fluid does not depend on the distance between the fish and is similar to the disturbance pattern from a point mass source.

Keywords

internal waves in the ocean; stratified fluid; school of fish; velocity field; numerical simulation.

References

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