On the efficiency of fish like swimming
Résumé
The aim of this work is to investigate numerically the efficiency of fish like swimming. We are interested in the Gray paradox stating that the power required for a fish to swim can be about seven times the muscular power available for propulsion. Even if this paradox has been contested in the literature it was confirmed experimentally at MIT. Our goal is then to perform numerical simulations of flow around a self propelled fish for several values of the Reynolds number. The Navier-Stokes equations are discretized onto a cartesian mesh and the interface between the fluid and the fish is computed using immersed boundary like method. The motion of the fish is computed in a Lagrangian way from the Newton's laws.